Originally Posted by
w0rd
You can join at an event or anytime on scca.com. It's like $75 and not worth it unless you enter more than 5 events per year for autocross.
I am not sure what an SCCA membership does for you on the road racing side.
Considering they do a lot of 2 day events, it doesn't take long to get 5 days in and make it worth your investment.