I stopped using Amazon a while back, but it was where I got all my books for a long time. I do thriftbooks mostly now, and try to buy directly from publishers when it’s a newer book, but I’m always interested in finding new spots to cop some sweet books.
Local library, archive.org, independent book stores, and bookshop.org
Audiobooks from library, libro.fm, deDRMed from my old audible library, and piracy