Another NoVA guy here. I'm up in the northern edge of Fairfax county about a mile from the Potomac river.
There is an active NoVA/DC/MD Porsche DIY/DE community that hangs out on
www.dorkiphus.net. Not a particularly Boxster friendly group, but they are slowly coming around as these cars are a darn good used car value and more of the Dorki's are picking them up.