In terms of taking the PCAT, I would suggest browsing through a review book and looking at the practice tests to see how comfortable you feel with the material. If you have been out of school a long while, or if you have never taken many science courses, you may need to review more. But, there aren't any specific courses you are required to take before taking the PCAT. Most schools recommend that you have at least one semester of Organic Chem completed, and maybe Calculus, before you take the PCAT.
As for applying to schools, all schools have their own pre-requisite courses (they typically vary slightly from school to school) - you should start looking at schools you might want to apply to and see what classes (if any) you are missing from their requirements. This will help you plan what classes you need over the next year or so.
Hope that helps a little!
