In the course of doing some research for the Pismo story, I came across the following items:

Town Gas: Evidently, natural gas was not in common use in the U.S. until after the Second World War. Each town manufactured its own gas– town gas– out of what was available: most commonly coal, but also rutabagas. (I would use rutabagas at any rate.)

Wood Gas: A cursory googling will yield a number of cars retrofitted to run on wood. Big tanks of wood.

Homemade Gasoline: This seems obvious in retrospect, but if you have a source of crude oil in your backyard and you rig up a makeshift still, you can make your own gasoline. It’s easier than making moonshine.