I am a book-a-holic too. I could probably do the same thing on Amazon that you do. However, I feed my book addiction with trips to the local Goodwill. I scan books to sell on Amazon, and when I'm buying books that are profitable, I also pick up books that I think look interesting and would like to read.
I've been doing this for a couple of years, and not only have I expanded my personal library probably two times over, I've made over $3,000 of straight-up profit. If you want to learn more about how I do it, send me a PM (I don't want to junk up your thread, which already has a lot of good ideas in it).