Where should I order books online from other than Amazon?

Every week a Guardian Money reader submits a question, and it’s up to you to help him or her out – a selection of the best answers will appear in next Saturday’s paper.

I’ve finally read all the books I have stacked up and want to buy more, but don’t really want to go to a bookshop. Where can I order from that isn’t Amazon? Are there any ethical options out there?

Do you have a problem readers could solve? Email your suggestions to money@theguardian.com or write to us at Money, the Guardian, Kings Place, 90 York Way, London N1 9GU.