Google Books has a "find in a library" link on some, but not all, of the books in their collection. This is odd because at a glance a lot of the works have ISBNs that could be turned into library queries. (Not all the books have ISBNs so it wouldn't be a universal search string).
I've taken the code from Jon Udell's Library Lookup and mashed it around until it inserts a link to my library's holdings of that book right on the Google Books screen. The useful bit of data is an ISBN number on some pages that can be turned into the link. If it is too old to have an ISBN, I punted; the better thing to do would be a title search.
Not done this go around: any kind of xISBN lookups. Sorry.
You can see the results here for the Ann Arbor District Library in this Greasemonkey script: Google Books Ann Arbor Library Lookup. It should be readily adaptable by anyone who has a copy of the Amazon library lookup for their library. A Flickr screenshot is here.