I've never tried to photograph car races before, and since there was a SCCA regional close by today I thought it was time to give it a shot. This track is 30 minutes from my house but I've never been there. I didn't know what kind of access I could get or if I'd even get one good shot, but I think these turned out OK. You can go pretty much anywhere you want - but there's a fence about 10' from the track when they're racing (close enough!). To give you an idea how close you can get, the cars leaving the grid area were shot with a 35mm lens (OK, about 50mm equivalent).
All shots on Fuji S2 with 20-35 or 80-200 2.8 Nikon lenses, JPEG. The blur shot is 1/30 at f22 - handheld... I actually found autofocus to do a great job, but the movement of a car is very even and predictable which helps.