No need for a lawyer, just take them to small claims.
http://www.courtinfo.ca.gov/selfhelp...cs.htm#howmuch
Yeah, you'll only get $7,500 but how much would a lawyer cost?
Once you win (with any luck) in small claims you can either garnish their wages or submit the judgement to the credit agencies and totally put the screws to them.
I just did this to a guy in Tennessee and he almost lost his house b/c he had an ARM that was about to blow up and CountryWide wouldn't give him the refi b/c he owed me. Needless to say the ass clown paid up.