B.O.B. has been around for a long time. I buy from them all the time. The only thing is under $5 purchases have a transaction fee so I only buy from them when I have more then that to spend. They have a rewards system which I love. I also like they have a cart system and they take PayPal.
I just recently started buying Audiobooks from them. I need to see if any of the ones I want are on sale because they are cheaper than Audible in most cases though the selection isn't as good.