Hey!! From what I know, and I haven't been playing all that long, it can vary from Campaign to Campaign. The next campaign we'll be starting (To our knowledge) is Rise of the Runelords, being hosted by DMRMZ.
In this one, it is the first post on the "Runelord, whacha wanting to play?" board, linked here. Although, if you don't have access to that, I'll list them right here.
1. All pathfinder books that the GM has reviewed. If you don't know if he has reviewed it , feel free to ask!
2. Confirmed large-books are the Core Rulebook, Advanced Players Guide, Advanced Race Guide, Inner Sea World Guide, Ultimate Magic, Ultimate Campaign, Ultimate Combat, and Mythic Adventures, as well as the Players guide for Second Darkness, Rise of the Runelords, and Kingmaker.
3. He also uses the Eberron Campaign Guide (From 3.5), but only the Races and Feats within.
When using 3.5 material, the pathfinder material overrides it if there is overlap. He will also be using the 3.5 Monster guides, and the 3.0 epic level handbook.
Currently, we are not using any Third Party Publications, at least to player knowledge. There haven't been any issues with Race or classes being banned or "not allowed," however I would let him know what your character is before you start the campaign, and keep in mind that if you look like a demon, paladins may have immediate issue with you, just like with any other race. Don't expect any free-passes just because you're a "civilized" monster.
Hope that helps! :) Good luck with the character building!