For many years, my favorite web site for purchasing books has been Best Book Deal. Not only does this web site offer the best book price from a great number of different book sellers, but it also includes the cost of shipping in the overall price, so it is possible to see at a glance the most economical place to purchase a given book.
And now Best Book Deal has added another search feature. If the book is available in digital format (primarily for Kindle), that price is also noted. So I found one recently published book listed this morning as a Kindle download for $9.99 and then I found another older work in the public domain that was available for as little as 99¢.
So if you have a Kindle, or another e-reader, Best Book Deal will now also help you find the cheapest price for those volumes as well.
Words of Grace 