As fourteener said,
http://bonsai4me.com is a great resource if you want to get some basic knowledge. The author, Harry Harrington, has three books out (at least), Bonsai Basics, Bonsai Inspirations I, and Bonsai Inspirations II. I have the latter two books as I had already read a lot about what he covered in Bonsai Basics. In the inspiration books he goes into detail on different techniques he used on different trees and each individual tree has a series of progression pictures to show you how he transformed them. Plus each different species he works on has a sort of cheat sheet with information on their specific needs and requirements. His books are much more detailed than the old books I found at my library. I definitely recommend both of them. The digital versions are both $9.99 a piece, or you can buy a paper copy for quite a bit more.