I just discovered this site... It looks like it could be very useful to find "hard to find" books which may be "hiding" in a library somewhere...
The web site is
WorldCat - http://www.worldcatlibraries.org
You can search for any author or title, and put in your location, and it will find the book you want in a library near you! It could save you some money (borrow books instead of buy them), or help you find a book that is impossible to find anyway (great for used and out-of-print books)...
Happy searching and reading...
Cheers,
Dien
P.S. For books which are
no longer copyrighted, you might be able to make money too by finding the books, and "republishing" them (either in print form, or as a PDF file)... Of course, do not do this for books that are still copyrighted (at least not without the permission of the copyright owner)...