The Library of Congress has a site to search books by ISBN. A simple way to retrive book's information is using a URL like:
http://lccn.loc.gov/2009019559/mods
where it returns a XML structure that may parse easily. The URL requires a unique LCCN number in the the following format:
http://lccn.loc.gov/[lccn]/mods
I have a batch of books that has ISBN encoded in barcode. How may I retrieve/convert ISBN to LCCN in order to retrieve the XML data of the book?