I'm not positive what available at Maxton (haven't run there in a year and a half), but at Bonneville there's usually some unleaded 100 and 104, and leaded 110, 114, 117, maybe some more flavors, too. All of the gasolines at the track are allowed in "gas" classes.
If you've got a specific favorite that's made by a different manufacturer -- for instance, you want to run VP -- consider contacting the sanctioning organisation and ask if they will allow you to bring a sealed-at-the-factory can of your flavor choice, open the can while under supervision, fill your tank while being observed, and then have your tank sealed. You might get away with it.
But -- the fuel vendors have a selection available, and since most of the racers will use track gas -- see if you can purchase a sample of the track gas before the meet, tune your motor on that fuel, and then support the venodr by buying from him at the track. That's a good way to do it.