I came across this web site www.paperbackswap.com.  It is basically a book swapping site.  You list the books you want to get rid of and when someone requests your book you mail it to them at your expense and in exchange you get (1 point) to choose any book you want out of the 1.3 million.   Now when you first join and list 9 books you want to get rid of you get 3 points good for getting 3 free books of your choice.  There is no cost to join or hidden fees.  Just the cost of shipping out your old book (between $2-$3) and getting your new book.  You can also have a wish list and if you are the one at the top when that book is posted, you will be notified and have 48 hours to accept or decline the book.  The site is super organized and you can see every book posted that day for any category you choose.  Several thousand of books are posted a day

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