Answering the original poster's question, I have no idea where the Corsairs get their H-fuel.
But, on board the diplomatic ship "Fallowed Ground" I spoke with Ze'ev about shipments of H-fuel to Tripoli in exchange for weapons. Don't worry guys, I've got it all covered. :cool:
Also, what about the Hogosha? They could easily make H-fuel shipments "disappear." Especially in exchange for the lucrative artifact trade.
Edited to add: So, to answer, a combination of Zoner and Hogosha/Alliance trade.
"The thirteen saloons that had lined the one street of Seney had not left a trace. The foundations of the Mansion House hotel stuck up above the ground. The stone was chipped and split by the fire. It was all that was left of the town of Seney. Even the surface had been burned off the ground.
Nick looked at the burned-over stretch of hillside, where he had expected to find the scattered houses of the town and then walked down the railroad track to the bridge over the river. The river was there."