Hi and welcome! A book that I swore by for a long long time was "The Complete Ball Python" by Kevin McCurley. He is the owner of NERD. I found that book was very informitive, and has a whole section about genetics that is an easy read. I have a copy that I would be happy to loan out to you, if need be.
Also, the Morphs and Genetics session here in the forum is very very helpful. Happy Breeding!