I just finished Roadside Picnic for the first time and dove into Robert Anton Wilson's "Sex and Drugs".

https://en.m.wikipedia.org/wiki/Sex,_Drugs_and_Magick

He talks about the difficulty in getting the book published in the early 70s:

"Playboy Press seems not to have published this book in the ordinary sense but to have released it on a need-to-know basis, or something of that sort. There were marvelous advance-of-publication blurbs from heavyweight figures like Alan Watts, William S. Burroughs and Timothy Leary; there were enthusiastic reviews in a dozen counter-culture newspapers and magazines; and then there was a stifled and prolonged silence, as if I had killed a cat in the sacristy. Every place I went to lecture or give seminars, people had heard of Sex and Drugs by word of mouth but complained that they were unable to find it in any bookstores. Very quickly, it went out of print. I have never earned a penny in royalties on it, which event I fully expect to reverse from the Falcon Press edition.

Even more curiously, as years passed and other books by me sold well and were reprinted regularly, no publisher was, for 13 years, willing to reprint Sex and Drugs. This has often puzzled me."