My friend gave me a bunch of books she did not want anymore. I knew I could not get much more than $1-2 for them, so I decided to list them on half.ebay.com. I have sold a few of them, and they too credit you for shipping. And the feedback from them helps with my Ebay feedback as well
The only problem I have with half.ebay.com is that when you confirm an item, you only have one business day to send it out... sometimes that is just about impossible!