The rules system we use is pretty vast, and thus, overwhelming. Instead of listing various books, cannon rules from Paizo. A source not available on line addition to that source, the Occult Players Guide is recommended as well.
Pathfinder Rules Website
The book of Occult rules is here.
(These rules are new, they are for Psychic Magic, a third type of magical energy that we will be using extensively in our game. Features 6 new base character classes)
PC sheets are here.
A PDF version of the core rule book is here. Please read it over.
For classes with casting abilities, use Perram’s Spellbook… and print yo’ self out some cards.
Lastly, the equipment book is here