Try this to find airport mogas.
http://www.flyunleaded.com/mapusairports.html
Leaded gas is pretty bad for aircraft engines, too, in most ways. ;-)
The rotary guys don't have to worry about octane (unless they run a turbo with a lot of boost), and most don't worry about ethanol, either. So most just run whatever pump mogas is within reach.
Charlie
Interesting map. In Texas, only 3 available. Guess I'll have to become my own tanker truck, hauling 5 gallon cans to the airport. This is what I did back in the 70's when I owned a C-172. It ran SO much better an auto fuel. But that is way before the EPA ruined the gas with the addition of alcohol.
edit: Just read that gasoline containing the dreaded alcohol MUST be avoided, as it will easily induce vapor lock.