Would a magical gauntlet (let's just say +3) give a +3 bonus for delivering a touch attack?
Here's the relevant rules I could find:
Touch: You must touch a creature or object to affect it. A touch spell that deals damage can score a critical hit just as a weapon can. A touch spell threatens a critical hit on a natural roll of 20 and deals double damage on a successful critical hit. Some touch spells allow you to touch multiple targets. You can touch up to 6 willing targets as part of the casting, but all targets of the spell must be touched in the same round that you finish casting the spell. If the spell allows you to touch targets over multiple rounds, touching 6 creatures is a full-round action.
Light: A light weapon is used in one hand. It is easier to use in one's off hand than a one-handed weapon is, and can be used while grappling (see Combat). Add the wielder's Strength modifier to damage rolls for melee attacks with a light weapon if it's used in the primary hand, or half the wielder's Strength bonus if it's used in the off hand. Using two hands to wield a light weapon gives no advantage on damage; the Strength bonus applies as though the weapon were held in the wielder's primary hand only.
An unarmed strike is always considered a light weapon.
Gauntlet 2 gp 1d2 1d3 ×2 — 1 lb. B —
Gauntlet: This metal glove lets you deal lethal damage rather than nonlethal damage with unarmed strikes. A strike with a gauntlet is otherwise considered an unarmed attack. The cost and weight given are for a single gauntlet. Medium and heavy armors (except breastplate) come with gauntlets. Your opponent cannot use a disarm action to disarm you of gauntlets.
If a gauntlet acts as an unarmed attack, aa touch spell requires an attack, and a gauntlet gives its magical bonus to an unarmed attack, i would say that a +3 gauntlets gives its bonus to touch spells.
edit: found this under combat:
Touch Attacks: Some attacks completely disregard armor, including shields and natural armor—the aggressor need only touch a foe for such an attack to take full effect. In these cases, the attacker makes a touch attack roll (either ranged or melee). When you are the target of a touch attack, your AC doesn't include any armor bonus, shield bonus, or natural armor bonus. All other modifiers, such as your size modifier, Dexterity modifier, and deflection bonus (if any) apply normally. Some creatures have the ability to make incorporeal touch attacks. These attacks bypass solid objects, such as armor and shields, by passing through them. Incorporeal touch attacks work similarly to normal touch attacks except that they also ignore cover bonuses. Incorporeal touch attacks do not ignore armor bonuses granted by force effects, such as mage armor and bracers of armor.
It looks like the gauntlet bonus would always apply if you are making an unarmed attacked, but is a touch melee attack affected by the bonus?
Ithink it could, but have found nothing saying it does.
I know in 3.5, you could make an unarmed attack to pass on the effect of a touch spell, but I don't remember the Pathfinder ruling on the same case.
Assuming we're not talking about Spiked Gauntlets, Gauntlets are (from the weapons table) "Unarmed Attacks". They are utilized during unarmed strikes, not touch attacks.
There are some ways to deliver your touch attack through an unarmed strike, but when doing so you must target regular AC, not touch AC. One way to do this is by using the rules on page 186, specifically "Alternatively, you may make a normal unarmed attack (or an attack with a natural weapon) while holding a charge."
If we're using a Spiked Gauntlet, that is a "Light Melee Weapon" in its own right, so you must have a way to channel your touch attack through it such as a Magus does.
Touch = no bonus, as you aren't attacking with the gauntlet.
Strike = enhancement bonus, as you are attacking with the gauntlet, but you are attacking regular AC instead of touch AC.