I've been exploring the same issues. Are you brewing extract or AG?
From what I gather, a book called (I believe) Designing Great Beers, explains the process of designing and creating recipes. Though I haven't read it, so I don't know if it deals with extract or PM.
I would recommend spending some time perusing the recipe section here. Try to recreate them and pay attention to what ingredients are used, and in what quantities they are present in different styles. Especially pay attention to the types of beers you are looking to make.