Not EMRA, but check out COM Sports Car Club.
We'll be at Summit Point (main), Watkins Glen, NHMS, in 2013, and likely return to Calabogie and/or Mosport and/or Tremblant and/or NJMP.
Tons of Miatas, if that is important to you (25-35% of the field), several competitive classes for Miatas too. Very friendly and welcoming club, talented & fast drivers, friendly competition. No wine or cheese or scallops wrappend in bacon, but killer BBQ and BYOB when the track closes. TT and Trophies at the end of day 2 (the time trial day). Day 1 is traditional HPDE type.
$100 discount for first-time partipants. Each track day earns you a $20 credit toward a future event. Non-profit club established in 1958 with decades of putting racers and track nuts ahead of profits <cough> NASA <cough>
Licensed groups, student groups, top-notch instruction.
Free transponders, your lap times are made available to you for every lap you run, if you want them.
COM Sports Car Club
I know a lot of people that 'used to run' with other groups. I don't know anyone that 'used to run' with COMSCC!
I am the chief instructor, so I'm a bit biased.