If you are one of the millions of us who are in the midst of a gradual transition from print books to ebooks, and it is one that involves downsizing your print book library, here’s something to ponder:

Amazon has just announced that they have expanded what they call their Textbook Buyback Program to include over a million titles, including hundreds of thousands of nonfiction and fiction books that are not, strictly speaking, textbooks. The program has been around for over a year, but until today’s announcement a relatively small percentage of titles were eligible. Just to give you a sense of the newly expanded range of this “textbook” program, all of the top 10 titles on the New York Times Hardcover Nonfiction Bestseller list are eligible and the average amount Amazon would pay you for them is equal to 44% of the discounted price for which the same hardcovers are available in Amazon’s main bookstore.

What’s great about this development, in addition to the wide selection of qualifying titles and the reasonably good prices being offered, is the utter simplicity of the program. There’s no need for you to become an Amazon Marketplace seller, to get into some kind of annoying daily shipping routine, to pay for shipping, or to sit around waiting for buyers to become interested in your books.

With the Textbook Buyback Program, you just follow a few simple steps, and you’re done. A few days later Amazon will deposit money into your Amazon account in the form of an Amazon Gift Card that will be automatically available for you to buy a brand new Kindle or Kindle DX, an Apple iPad, your choice of Kindle books, or anything else in the Amazon Store. Easy as 1-2-3:

1. First, go to the Textbook Buyback Program page and enter the ISBN to check price and availability. It’s your choice whether to send off a single book or a boxful.
2. When you’ve finished entering the books you want to send back, Amazon will prompt you to print a shipping label so that you can package and ship your books free of charge.
3. Check your inbox and your Amazon account for your new gift card(s), and you could be on your way to a free Kindle, iPad, or other item(s)!

Here’s the guts of Amazon’s press release this morning:

Over 1 Million Books Now Eligible for the Amazon.com Textbook Buyback Program

Just in time for the end of the semester, customers can now choose from over one million books to trade in for high prices at Amazon.com

SEATTLE, May 10, 2010 (BUSINESS WIRE) –Amazon.com, Inc. (NASDAQ:AMZN) today announced that over 1 million books are now eligible for the Textbook Buyback program, which allows customers to quickly and easily exchange used textbooks in return for an Amazon.com Gift Card. Available year-round, the Textbook Buyback program offers students the ability to trade in textbooks they no longer need for a high price. For more information about the Textbook Buyback program, visit: http://www.amazon.com/buyback.

Textbook Buyback offers great prices on over 1 million eligible titles. Not only is it easy to use, but students can avoid long lines at the bookstore and trade in their textbooks from their dorm rooms or from home without facing buyback deadlines. Students just visit www.amazon.com/buyback, and search for the books they want to trade. Then students can print a pre-paid shipping label and drop the package in the mail. Once the book is received and verified by the third-party merchant that purchases the titles, an Amazon.com Gift Card will be deposited into the student’s Amazon.com account. This gift card can be used toward the purchase of next semester’s books, or the millions of other items on Amazon.com.

“With a great selection of titles, low textbook costs and high prices for Textbook Buyback, we continue to make the Textbook Store an easy and economical option for our student customers,” said Julie Todaro, director of Books at Amazon.com. “Buying textbooks is no longer the financial burden it once was for students, and we’re happy that we’ve been able to make Textbook Buyback even more convenient with over 1 million books now available to trade in for high prices. Students are crazy if they’re still selling their books back on campus.”

The Amazon.com Textbooks Store (www.amazon.com/buyback) helps students manage the high cost of textbooks by offering savings of up to 30 percent off the list price of more than 100,000 new textbooks and up to 90 percent off the list price of millions of used textbooks.