Although not quilt related, directly it could be indirectly.
I know many of you use your local library for quilting books instead of buying them. I do this also. I was surfing the net looking for a book and ran across this website.
http://www.worldcat.org/ you put the title of the book you are looking for in the search and then it will find that book in your nearest library according to your zip code. I found several books that my "local" library doesn't carry, but I can go to the next town over and check them out for free using my local library card because they have a Co-op. Way easier than having to check each libraries catalog one at a time.