Are you looking for fiction? It isn’t perfect, but the kobo store has information near the bottom of every book’s page letting you know what level (if any) of DRM that a book has, so you can factor that in to your purchase decision. For drm-free files, you can download epub files directly once you purchase. Outside of that, I use Project Gutenberg, Baen, and a few other niche publisher websites. Basically, if you want to purchase content that you can use freely you just have to make the best of a bad situation.
Are you looking for fiction? It isn’t perfect, but the kobo store has information near the bottom of every book’s page letting you know what level (if any) of DRM that a book has, so you can factor that in to your purchase decision. For drm-free files, you can download epub files directly once you purchase. Outside of that, I use Project Gutenberg, Baen, and a few other niche publisher websites. Basically, if you want to purchase content that you can use freely you just have to make the best of a bad situation.