From their site: ISBNdb.com's remote access application programming interface (API) is designed to allow other websites and standalone applications use the vast collection of data collected by ISBNdb.com since 2003. As of this writing, in July 2005, the data includes nearly 1,800,000 books almost 3,000,000 library records close to a million subjects hundreds of thousands of author and publisher records parsed out of library data more than 10,000,000 records of actual and historic prices. Using the API you can look up information by keywords, by ISBN, by authors or publishers, etc. In most situations the API is fast enough to be used in interactive applications.
The following is a list of how-to and tutorial content that matched your search term. ProgrammableWeb's how-to content comes from two sources; full-blown tutorials that we publish ourselves and other highly relevant tutorials that we find elsewhere on the Web. This list represents on combination of both tutorial types and if you go to ProgrammableWeb's API University, you'll not only be able to find more, they are organized based on your role (API providers or developers who consumes APIs). If you know of a tutorial that would be of interest to the ProgrammableWeb community, we'd like to know about it. Be sure to check our guidelines for making contributions to ProgrammableWeb.