I think I might have all of his books, and I've read every one of them. It's been 20 years though. Some of them are out of print. He was from the 60s, a contemporary of Timothy Leary, writing about psychedelics and the limits of belief, how to change your brain and the way you think. He wrote about conspiracy theories more as a form of entertainment, back when they were talked about in self-printed journals. He died 11 years ago. I talked to him on the phone once over 20 years ago. He used a fake name but he had a very distinctive voice.

For his fiction books, I would start with the Illuminatus Trilogy. For non-fiction, maybe Prometheus Rising.