I said this elsewhere -- will repeat it here.
The OHV rule is a state of Utah rule, not federal, so don't sweat the BLM officers that are meandering around. Do watch out for state, local, or county police. I'm told there'll be at least a pair of them in and around the pits this Saturday (don't know about anything earlier), so be careful then.
If you don't have your permit and buying one is what you're planning to do, there will be two local points where you can buy: at the West Wendover Visitor Center and at the Metro (the real name for the truck stop where Marcello's Salt Flats cafe is located). The permit will set you back $30. I don't know how much a ticket will cost. I don't expect to find out except through hearsay.
To get one of the permits you will need both personal identification (driver license, passport) and some proof of ownership of the chosen vehicle (title, bill of sale).
There are, at present, no firm plans to require registration to use the potties. That's still in the early stages of discussion.