Pathfinder doesn't really use Level Adjustment, but has rules for monster as PCs (that can be a bit complicated).
My suggestion is to get the Advanced Races Guide (or wait till D20pfsrd gets it) and stat up the LA race with the rules there. Once you figure out how many points a stock version of the race is worth, start cutting out abilities until you get something that is worth 9-11 points and still looks like the original.
Alternatively, you can set the base line at more than 10 points and have the other races buy a number of alternate racial abilities without trading anything away until they are more inline with the more powerfull race. I don't recommend mixing races of different power levels unless you are ready to eye-ball the LA manually on a level-by-level basis.
I'll do the centaur as an example:
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Defining centaur abilities from the PRD priced with the ARG
7 RP - Large Sized
3 RP - Monstrous humanoid
o RP - Normal Speed
4 RP - Advanced ability scores (+2 physical, +4 wis, -2 int)
20 RP - Advanced abilities x5 (all but wis) :p
2 RP - Natural armour (1 NA)
1 RP - Improved natural armour (+1 NA)
2 RP - Improved natural armour (+1 NA)
3 RP - Improved natural armour (+1 NA)
4 RP - Improved natural armour (+1 NA)
5 RP - Improved natural armour (+1 NA)
1 RP - Fast (+10 ft movement)
2 RP - Quadruped
----
54 RP, not counting Racial hit dice
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We can drop a lot of this stuff and get a "centaur-y" feel. There is a 28 point version in the ARG, so I'll give you a 10 point version that should be usable along side elves and dwarves.
7 RP - Large Sized
0 RP - humanoid
0 RP - Normal Speed
0 RP - Standard ability scores (+2 con, +2 wis, -2 int)
2 RP - Natural armour (1 NA)
2 RP - Quadruped
----
11 RP
This plays fast and loose with some of the requirements, like quadruped requires a monstrous humanoid type and can't be given to standard races. However, Its always bothered me that every creature that is a monstrous humanoid simply must have darkvision. I figured that since they have human-ish heads, they may as well suffer from human-ish vision.
Personally, I've always found Natural armour to be a boring racial ability. So even though it would not quite match the original centaur, I'd replace natural armour bonus with either Endurance or Run as a free bonus feat.
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Put together, this gives you a race that looks like this:
Ability scores Centaurs are worldly and tough, but they don't stay in one place long enough to become scholarly (+2 con, +2 wis, -2 int)
Size Centaurs are large sized. However, because their bodies are medium, they only wield medium weapons. This gives them a -1 size penalty to AC and to hit, and -4 penalty to stealth.
quadruped Centaurs have 4 legs. This gives them a +4 racial bonus to resist trip attempts
Base speed Centaurs have a base speed of 40 ft
languages Centaurs start with common. Centaurs with high Intelligence scores can choose from the following: Elven, Dwarven, Orc and sylvan.
Plains runner Due to horsey hindquarters, centaurs gain Run as a bonus feat.
Mountain master Some centaur have adapted to life in the mountains. They are more resistant to the cold weather and the thin atmosphere.
there is a centaur on page 218 of the ARG, it's 28 RP.
My suggestion is to get the Advanced Races Guide (or wait till D20pfsrd gets it) and stat up the LA race with the rules there. Once you figure out how many points a stock version of the race is worth, start cutting out abilities until you get something that is worth 9-11 points and still looks like the original.
Alternatively, you can set the base line at more than 10 points and have the other races buy a number of alternate racial abilities without trading anything away until they are more inline with the more powerfull race. I don't recommend mixing races of different power levels unless you are ready to eye-ball the LA manually on a level-by-level basis.
I'll do the centaur as an example:
----------------------------------
Defining centaur abilities from the PRD priced with the ARG
7 RP - Large Sized
3 RP - Monstrous humanoid
o RP - Normal Speed
4 RP - Advanced ability scores (+2 physical, +4 wis, -2 int)
20 RP - Advanced abilities x5 (all but wis) :p
2 RP - Natural armour (1 NA)
1 RP - Improved natural armour (+1 NA)
2 RP - Improved natural armour (+1 NA)
3 RP - Improved natural armour (+1 NA)
4 RP - Improved natural armour (+1 NA)
5 RP - Improved natural armour (+1 NA)
1 RP - Fast (+10 ft movement)
2 RP - Quadruped
----
54 RP, not counting Racial hit dice
1) you are forgetting Point Buy before Racial Adjustments (and a +1 somewhere for the 4th hit dice.
2) it only has +1 nat armorAnd seriously 28 RP isn't that bad considering all the desavantages; your gears cost way more, your gears weight way more, a Centaur is/can be hard to fit as a PC (and in openings, doors, doorways, etc...).
And
Quadruped(2RP):Prerequisites:Any type except humanoid, Large size, normal speed;
sorry.
1) you are forgetting Point Buy before Racial Adjustments (and a +1 somewhere for the 4th hit dice.
2) it only has +1 nat armorAnd seriously 28 RP isn't that bad considering all the desavantages; your gears cost way more, your gears weight way more, a Centaur is/can be hard to fit as a PC (and in openings, doors, doorways, etc...).
1) The centaur does not have class levels. So its point buy is 11,11,11,10,10,10. I thought only NPCs get the basic array.
Even if I'm wrong, The centaur still has +2 or more in every stat. If it had 13, 11, 12, 9, 10, 8 then It would need two more Advanced Abilities in int and cha, instead of 2 in strength and con. This would have cost him 2 points more.
2) Oops, good catch. I miss-read "armour" as "natural armour." I seem to have forgotten they had equipment. That saves 14 RP.
Quadruped(2RP):Prerequisites:Any type except humanoid, Large size, normal speed;sorry.
Err, I know. You will notice I wrote:
This plays fast and loose with some of the requirements, like quadruped requires a monstrous humanoid type and can't be given to standard races. However, Its always bothered me that every creature that is a monstrous humanoid simply must have darkvision. I figured that since they have human-ish heads, they may as well suffer from human-ish vision.
I wanted it to be a 10 point race and I wanted it to have a little more than just Quadruped. Being a monstrous humanoid is too good for a base race anyway since it makes you immune to a bunch of spells. Also, it makes no sense for plains-dwelling horse-people to have dark vision. I wish that the creature types didn't have to come bundled with so much baggage.
In any case, the OP wanted a playable centaur race. I think this version is not broken and is more useful than saying "No. You can't do that."
Incidentally, I think that Large + quadruped should probably give you a discount, not cost 2 points. You gain a bonus to CMD, speed (which is worth 1 RP) and carry weight. In return, you lose the best parts of being large, that is reach and weapon size. In exchange, you are stuck with AC and attack penalties. At the very least, I think that being a quadruped (and having a medium body) should remove the attack penalty. Though this is all pure theory-craft. I haven't tried it in real games.
Just a thought on centaurs. You may want to treat them as if they had Mounted Combat for the purposes of pre-reqs. Also, its a bad idea to actually let them take mounted combat and dodge one attack per round.
The following copied and pasted from a similar thread:
If the monster PC guidelines in the Bestiary are strictly adhered to, a centaur PC's progression looks like the table below. The left column shows the centaur's racial HD (before the slash) and the centaur's class levels (after the slash) as it compares to his more normal party members' class levels. For example, if your party is 16th-level, then you should be a 14th-level centaur (that is 4 HD & 14 class levels). The bolded line is where the centaur gains a "bonus class level" to make up for his inferior racial HD.
4/00; 3
4/01; 4
4/02; 5
4/04; 6
4/05; 7
4/06; 8
4/07; 9
4/08; 10
4/09; 11
4/10; 12
4/11; 13
4/12; 14
4/13; 15
4/14; 16
4/15; 17
4/16; 18
4/17; 19
4/18; 20
Your centaur racial traits would look something like this:
Ability Modifiers: +4 Str, +4 Dex, +4 Con, +4 Wis, +2 Cha (as well as +1 to any one ability score for your 4th racial HD)
Size: Large (10 x 10 ft.)
Type: Monstrous Humanoid (4 HD)
Speed: 50 ft.
Reach: 5 ft.
Armor Class: +1 natural armor bonus
Natural Attacks: 2 hooves (secondary attacks, base 1d6 damage)
Skills: No racial bonuses, but you get a +8 bonus to Acrobatics checks made to jump due to high speed.
Special Attacks: none
Special Qualities: Darkvision 60 ft., Undersized weapons
Starting Languages: Common, Elven, Sylvan (with no bonus languages for high intelligence)
You may only play such a character in a 3rd-level or higher group and you gain the starting funds of a character for your effective level (for example, if you started in a 16th-level group, you would start with 315,000gp worth of adventuring gear).
HP: 10 + 3d10 + (con x 4)
Base saves: +1 Fort, +4 Ref, +4 Will
Base Attack: +4
Bonus Armor/Weapon Proficiencies: All light and medium armors, shields (except the tower shield), and all simple weapons plus the longsword
Feats: 2 general feats (one at your first HD, and one at your 3rd)
Skills: You have 16 ranks to assign (modified for intelligence) and you can have up to 4 ranks in any given skill. Your class skills are Climb, Craft, Fly, Intimidate, Perception, Ride, Stealth, Survival, and Swim.
When you add on class levels, you follow all the same rules for multiclassing (thus you do NOT gain max hp for your first class level since you already got it for your first racial HD). You can also start benefiting from your favored class bonuses (as you can't choose your racial type as a favored class).
That's about it I think. If you have any other questions about playing monstrous characters, feel free to let me know.
EDIT: Don't forget your size modifiers (-1 AC/attacks, +1 CMB/CMD, -4 Stealth, etc.)
But if you want a 0 HD version of the centaur, I recommend looking to the Advanced Race Guide race creation system for starting guidelines.
Just to add to RD's centaur write-up. You don't actually get max HP for your first racial hit die. Source.
1) you are forgetting Point Buy before Racial Adjustments (and a +1 somewhere for the 4th hit dice.
2) it only has +1 nat armorAnd seriously 28 RP isn't that bad considering all the desavantages; your gears cost way more, your gears weight way more, a Centaur is/can be hard to fit as a PC (and in openings, doors, doorways, etc...).
1) The centaur does not have class levels. So its point buy is 11,11,11,10,10,10. I thought only NPCs get the basic array.
Even if I'm wrong, The centaur still has +2 or more in every stat. If it had 13, 11, 12, 9, 10, 8 then It would need two more Advanced Abilities in int and cha, instead of 2 in strength and con. This would have cost him 2 points more.
Centaur stats: Str 15, Dex 14, Con 15, Int 11, Wis 14, Cha 12
The ARG breaks this down as:Flexible Ability Score Modifiers (+2 Str, +2 Wis): 2 RP.
Advanced Constitution (+2): 4 RP
Advanced Dexterity (+2): 4 RP
Advanced Strength (+2): 4 RP
Large (+2 Str, -2 Dex): 7 RP
This produces mods of +6, +0, +2, +0, +2, +0.
But the stats need mods of +4, +4, +4, +0, +4, +2.
So yeah... The ARG centaur will not build a Bestiary centaur, unless you use a stat array of 9/14/13/11/12/12.
Just to add to RD's centaur write-up. You don't actually get max HP for your first racial hit die. Source.
Interesting.
Has their been a ruling in regards to the bonus ability score points for racial hit dice (for every 4 HD)? I think I recall hearing that it was assumed in the creature's stats and that you weren't supposed to add it in, on a monstrous character.