$60 for an evening 5:30 until dusk at GingerMan. You can usually burn a tank of gas on track.
MCSCC has high speed timetrials events that cost $85-100 to enter which includes beer after track closes. Usually only 2 or 3 ten minute practice sessions in the morning and 4 timed runs after lunch, so track time is somewhat limited. They run at Blackhawk Farms, Autobahn, Milwaukee Mile, and GingerMan.
I've attended and taught for just about everyone over the years. My first few events were thru professional schools - TrackTime and then Car Guys. Once I got those, I started looking for cheap seat time...the Porsche clubs normally offer some of the cheapest track time you can find...partially because they also charge(d) their instructors too!! Most of the prices were around $175-300 depending on the track and how many days it was. Most of the club schools now are around $250-400 and the 'pro' schools range from $450 and up.
The club school instructors as a whole aren't normally screened as well as the pro schools so it's a crap shoot as to who you get and if they are any good. Most of the pro school instructors have more time on track and quite a few also have plenty of wheel-to-wheel racing experience.
Last October a local guy trying to sell Radicals had a private track day. I believe I paid $200. Two groups- experienced and novices. I ran experienced. I went through two complete tanks of gas. I was on track so much I got sick and almost heaved. The sessions were so long I only completed the first two. After that I would pull in after 25 or 30 minutes. Basically there were no rules, but everyone behaved. I was out there with two team-based GT3 Cup cars. It was interesting going into turns 6 and 7 two-wide with one or both of the GT3's. I was turning in the low 1:30's they were turning in the 1:19 to 1:20's. I think I learned much more being out there solo for so long than I ever did at a normal DE event where we only get 4 20minute sessions per day. The best part of the day was one of my neighbors showed up in his Lambo that he always bragged about. He was always saying how we should race sometime. I never responded to him. He doesn't comment on his car anymore. It was no-contest.
$100 for one day of trackage, four sessions, 30, 30, 30 and 45 minutes. Part of Rolling Thunder at Texas World Speedway. This was the test and tune thing before the autocross weekend. Quality track time on a fast course.