To learn genetics, you should start with a textbook. Schaum's Outline of Genetics, by ? and Stansfield (either 3rd or 4th edition) is inexpensive and gives the best bang for the buck that I know of. That will give you a grounding in terminology and principles. The principles are the same for mice, fruit flies, corn snakes and corn plants.
I advise against trying to learn genetics off the web, One exception to this general rule is www.ringneckdove.com. It has some very useful stuff on it once you have the basics. And www.serpwidgets.com is about the best corn snake genetics web site I know of. But most of the rest are the equivalent of shooting yourself in the foot.
Breeding high quality morphs requires experience and a good eye for detecting what makes a quality herp more than book learning. Good luck.
Paul Hollander