I have done a few events with the SCCA Washington DC region (WDCR). Their events are fairly well run, but they tend to do Summit Point Shenandoah circuit, or maybe Summit Point Main. I have not seen them so farther afield to VIR or NJ Motorsport Park. I am already an SCCA member for auto-x, so it doesn't cost me anything to do trackdays with them, too.
I have done a few days with the Potomac chapter of the Audi Club. They run really good events. Usually they are two day events, and they like to go to VIR. Good quality t-shirts, Saturday night dinner with an auction of sponsor goods, on time, etc.
My brother does a lot of stuff through Trackdaze. I don't think there is any membership involved, they are just a good resource for events. They have events listed for VIR, Summit POint, NJMP, and Road Atlanta on their page right now.
'04 BMW 330i ZHP
'02 Mercedes G500
'08 Audi TT Roadster