A great link to download opensource books. You can get many Psi; Magick, or any other books you might find on Amazon for free. You can even find many out of print books to build your library:
Yeah, I had lost like 95% of my occult library, which took years to accumulate because the hard drive I had it on died. Anyway, I've been furiously downloading Eastern cultivation & Western Magick books I used to own.
That's frustrating. I've got hard drives with duplicates in case one dies. Some in RAID 5 and others just standalone drives. I've lost so many things over the years I'm a tad paranoid.
I just wanted to add, z library is still alive and thriving. The front end of the site got taken down a few months back but you can find the official url from the z library sub reddit. The developers even made an android app so you can side load the apk. There are a lot of scam sites pretending to be z library though so make sure you are using the correct link. There are tons off old occult books that are not available to purchase anymore. I don't know how much overlap there is with Anna's archive but I really like the UI of zlib for personal preference. The app got updated and has a new feature where you can read the books online without downloading them if you wish. ^_^