I don't have enough of the books to suggest for v3.5.
However, v3.0 has the Masters of the Wild splat book. That had quite a few that I really liked. (Foe Hunter is one of my favorites.) Most would translate to v3.5 with almost no changes necessary.
Yeah, I have Complete Warrior... Nature's Warrior would be the nearest fit, but the player for whom I'm trying to find a PrC isn't into shape-shifting. His Ranger (who is human) is more into sharp-shootin', or else stalkin' and trackin'.
Masters of the Wild I had completedly forgotten about--I'll have a look.
Ifthe character focus on archery, there's Highland Stalker in Complete Adventurer and Order of the Bow Initiate in Complete Warrior. If he's into hunting down a quarry, there's Bloodhound (Complete Adventurer), Consecrated Harrier (Complete Divine) and Justiciar (Complete Warrior). If he wants to focus on his animal companion, there's Beastmaster and Wild Plains Outrider (Complete Adventurer).
Horizon Walker (DMG) gives full BAB progression, and significant bonuses to traditional Ranger skills for levels 1-5, with some great goodies at levels 6 and up.
I just made a horizon walker. I've found it to be much more satisfying than I would have thought. While it does little to expressly assist a ranged combatant, the special abilities it grants are very ranger-appropriate.