For those looking to get some W2W action up at BIR, WRL is a new series but run by the same guy that ran ChumpCar's Central Region the last four years (Joey Todd). The rules are so simple compared to almost any of the racing series and has classing (power to weight) so you always have someone to race against that is similar.
The series is set up to allow anyone with a car from Lemons, ChumpCar, SCCA, NASA, Vintage, etc. to participate. It's intended to run what you have instead of complicated rules.
Many folks have already signed up and there is everything from a detuned Corvette to a Hyundai with other cars including Lexus, Dodge Neons, VWs, BMWs and a Ford SHO.
The "early in" registration ends May 1st but you can register after that, it just will cost a little bit more. The fee covers a transponder as well so it's a great deal.
I've run in Joey's events all over the middle part of the US from BIR to Texas World Speedway. He goes out of his way to welcome all and his events are very well organized. The series has been reviewed in Grassroots Motorsports and their first event was a huge success.
Website here: http://www.worldracingleague.org/
Rules here: http://www.worldracingleague.org/pdfs/WRL_RULES.pdf