Again, I thank my husband for discovering cool things for me on the internet. This time it is an extensive book search engine. Typically I assume the best prices are to be found on Amazon, but this search engine has proved me (sometimes) wrong. It claims to search 130 bookstores and 80,000 booksellers then gives you a breakdown of prices with postage included. It is especially helpful for my husband who needs rare or out-of-print books. We'll be on a first-name basis with the mailman soon.