I used to go to events all the time and they had magnetic stickers on the sides of the cars that didn't care about giving a ride. The magnets said "Autocross Taxi."
I also had a friend who was first in a super modified class running a 1991 Miata. He had his tire pressures monitored, changed out the oil before each race, etc. He was fanatic. He never offered rides because he knew the way the car handled with his weight and if a human body was in the passenger seat, he'd have to change everything. It wasn't in vain because like I said, he was first for like 3 years straight.
To me though, that doesn't seem like much fun. I'd be good with just going to novice for a while. Just a place to let loose ya know. Also, Toyota claims the XR can handle as good as the 350Z. Supposedly, I think the Sittin Sic kit claims they can make that claim become reailty. Thoughts on this claim since I've not had a chance to really open her up since I got her.