The last guy's alluding to right wing books though. I remember Axios reported that the Turner Diaries and Camp of the Saints are going for hundreds now, because printing has been ended: https://www.axios.com/2021/01/28/racist-novels-skyrocket-in-... But books are now available on Amazon for cheap and pirating is easy, but here are some which libraries don't seem to have stocked and mostly aren't purchasable.

I imagined Holocaust denial etc. are effectively banned/not stocked by most libraries. Googling, I found discussions about My Revolutionary Life by Leon DeGrelle, Into the Cannibal's Pot by Ilana Mercer etc. But things from other movements too like an Ulster loyalist Ian Paisley's Messages from the Prison Cell or Uncomfortable Questions for Comfortable Jews by Rabbi Meir Kahane. Pinochets memoir is also inaccessible.

Then there are books about bombs or e.g. Put em Down, Take em Out by Pentecost about knife fighting ($60/now used). In the UK, a nazi was jailed 13 years for having a pdf the White Resistence Manual: https://www.itv.com/news/calendar/2023-08-31/prison-officer-...

I'll stop there. There are long lists, with about half the entries seeming plausibly banned.