Robby Gordon owns and operates the series. It's a spec class that's invite only, but still a ton of fun and competitive. I've seen them run a few times, most recently at Mid-Ohio last year as a support race during the Indycar weekend. The series has an interesting history, Robby conceived it to run large stadiums around the US, in the spirit of the old Mickey Thompson indoor off road races. After a modest first season, they found greater success running as a support race for major series in the US and Australia.

http://stadiumsupertrucks.com/