Avid readers looking to bulk up their library or check books off their list will want to head to the Used Book Superstore in Burlington.  One of five locations, this store has hundreds of thousands of books for a shopper's browsing and buying pleasure.  All books are priced at $2.99 or less, shelved on row upon row of categorized stacks.  For the customer who can't wait to get home before digging into his or her new purchase, there are many chairs and couches scattered throughout the store.  For children there is a small play area in the corner of the store near the children's selections.  There are also Melissa and Doug puzzles and toys for sale.  Donations of books can be made, with proceeds going to RARA, an organization that assists challenged adults.