As has been noted, blink's been nerfed, you want Gtr Invis.
There are a few conditions that make opponents flat-footed:
1- Blinded: Blindness; Tiefling (Darkness 1/day + Darkvision); Blindness/Deafness (as above); Sniping etc. Included in this is Gtr Invis, this really is the most consistent means for a ranged rogue.
2- Cowering: With 3.5 you could make an Avenging Executioner/Ghost-Faced Killer build that did this mercilessly; in Core PF you're left with relying on casters to help you (Cause Fear, Necromancy spells).
3- Paralyzed: Again, get your party caster to memorize Hold Person/Monster. I'll put the lowly Sleep spell in here, Coup de Grace + Sneak Attack = XP.
4- Pinned: Obvious.
5- Stunned: Monks are your friends.
6- Off Balance: Grease; 1st lvl spell, 750 gp for a wand. This should suffice where you know your opponent is gonna move. For archers/casters don't bother, it doesn't work unless they move.
Tailor your feats/magic items to create these conditions and you're laughing.
The most effective ranged rogue hands down is the Arcane Trickster. Take the Illusion school as your specialty and when it counts you're invisible. Enemies that have See Invis. or Blindsight then need more condition based tactics.
Hope that helps :)