If you're looking for an alternative to Amazon, try the wonderful independent bookshop, News from Nowhere.
I promise, I have NOTHING to do with them. @MNHQ This is not a spam post. Just that I've had several orders of feminist books from them, as well as other books (the final Wainwright for my walking collection) and their prices are excellent, and the service was personal, friendly and fast by mail order.
I've also used Hive, as another alternative to Amazon, but their range of books isn't quite so good. I was very impressed with News from Nowhere as a small independent co-op and what they could find for me.
Just wanted to spread the love a bit. Radical feminists need it at the moment, let's face it!