typically, i follow the mazda sportscar owner's club MSOC events. They call it PITL, Push it to the Limit series. I haven't seen anything listed yet for their 2008 season though. There's also HADA, and the corvette club, and a couple others. I suppose if there's some interest, I'll post the events I hear of, and which I'll likely attend. (hopefully with some other diesels to help me smoke the competition!)
I just ordered new tires today, and with some suspension adjustments, a turbo-back mandrel bent 3" exhaust, and actually hooking up my intercooler, I should be a tad more competative this year! I've got a grudge against a certain miata. (the one that eliminated me from the competition this video was taken at)
Should be fun this year!