Evolution all-day autocross school may be coming to your nearborhood at some point...
The Evolution Performance Driving School - Building Champions since 1993 - Autocross, Driver School, HPDE, License
Your local SCCA region may also have educational events, or instructors who can ride along and critique your driving, or drive you car while you watch and observe and learn.
I'm also just curious, what modification(s) did you make already which put you into
SCCA Street Touring Unlimited class?