The FAQ should be able to help you, but there's something I want to clear up real quick: there's a big difference between the mechanics and the brand. The mechanics are covered by the OGL, so you can use them all you want as long as you abide by the terms of the OGL. The brand, however-- the Pathfinder name and logo, the iconics, et cetera.-- is not covered by the OGL and the OGL does not allow you to use any part of it.
Paizo offers a separate license for using the Pathfinder brand. I'm not familiar with the license myself, but if you want to publish Pathfinder material... you make certain that you are.