And now there's Google Print
Link - "To use Google Print, just do an ordinary Google search. For example, when you search on "Books about Ecuador Trekking" or "Romeo and Juliet," and we find a book that contains content that matches your search terms, we'll show links to that book at the top of your search results. Click on the book title and you'll see the page of the book that contains your search terms, as well as other information about the book. You can also search for other topics within the book. Click "Buy this Book" and you'll go straight to an online bookstore selling it. If the book was scanned from a library, click the library link to find a local library that has it.
Right now we're just testing this program, so you may not see books in your results for every search. But you can expect to see more and more books popping up in your search results in the coming months. If you're a book publisher and you'd like to have your books included in Google search results, look into the Google Print program for publishers."