Comment by jrmg

Alibris (https://www.alibris.com/) is a great alternative. I do basically all my book buying there.

If anyone’s concerned about the condition of used books, I’ve found their condition descriptions (https://www.alibris.com/popups/glossary/book-condition) to be reliable (indeed, books are often in better condition than indicated - I’ll happily order anything ‘fair’ or above).