Try Jiu Jitsu, it's not overly hard to learn so long as you apply yourself. It takes a street fight to one of the few places an attacker would expect it to go, to the ground. Grappling, submissions, joint manipulation, Etc. The gracie schools are a good place to start, so long as there is one in your area.
www.relsongracie.com
This site has a list of some of the schools around the US.