Chris the Librarian and arendallsalvetti both mentioned a limitation of Jon Udell’s Library Lookup bookmarklet. The bookmarklet searches by ISBN number, and since ISBN numbers are associated with a particular version of a book (hardcover, paperback, large print, etc), the bookmarklet will only check for a particular version of a book, and not for any version of the book.

Both LibX and BookBurro will search for any version of a book at your local library. I am not certain how BookBurro does this, but LibX uses OCLC’s xISBN service. Jon Udell wrote a follow up post about a Greasemonkey version of Library Lookup that used the xISBN service:

http://weblog.infoworld.com/udell/2006/01/30.html

But since Jon wrote this Greasemonkey script, OCLC created a simpler interface that will query your local library for all versions of a book using just a single URL (instead of diving into all of the AJAX and DOM parsing issues Jon documents in his second post). If your library uses a supported OPAC (Online Public Access Catalog) and you can extract an ISBN number from a page, then you can search your local library for any version of a book using a URL that looks something like this:

http://labs.oclc.org/xisbn/liblook?baseURL=http://catalog.lib.rochester.edu&opacID=voyager&isbn=0613915313

If you know a little bit of JavaScript, it shouldn’t be hard to modify Jon’s original Library Lookup bookmarklet to use the xISBN service and search your local library for any version of a book.