it's probably going to be a month or two before i get to the track catalog for these areas, i was planning on taking care of the southwest before swinging to the north atlantic and northeast. i suggest looking for links and contact info from these sites:
http://kidkarters.com/track_map.htm and
http://www.speedwaysonline.com/ as a starting point.
i also think it would be interesting to add 'rental available' to kart track directory entries when i can figure that out. i may well do that. the big problem is that it's hard to find that sort of stuff out researching with google, a lot of facilities have very thin online presence.