I'll ass to what Mr. Stainless, sir, advises:
A couple or five years ago a nitrous vendor was at one of the events at Bonneville to test the market, so to speak. He wanted to see if there was enough demand to justify him being there on a regular basis. He never again showed up. Take that for whatever you want - that he was a lying SOB or there wasn't enough demand/too many of the racers brought their own with them or the fees he would have to pay to the sanctioning body were too high or he had a death in the family -- but he hasn't been there again.
Rick Gold in the ERC fuel truck/compound does NOT have nitrous for sale. There are a few racers that have been gracious enough to fill a bottle here and there for me over the years, but since it was as a favor and not for sale -- I won't name him here. If you find me on the salt I'll show you the pit where said nitrous guy hangs out and you're welcome to ask him then.
As far as I know there is no source in the greater Wendover metropolitan megalopolis - other than maybe Painless Pete.
