Books

Book Sale Finder
Guide to used book fairs and sales across the USA.
http://www.booksalefinder.com/

Centre for the History of the Book
History, projects, and events.
http://www.hss.ed.ac.uk/chb/

International ISBN Agency
Includes a user's manual, prefix ranges, details of group agencies, publications, reports, and news.
http://isbn-international.org/

ISBN Tools
Information and tools for using International Standard Book Numbers. Scan them with a CueCat, look them up, or search them.
http://isbntools.com/

ISBN.org
Enables applications to be made for ISBNs, SANs, and ISMNs in the United States and Puerto Rico, and provides information about the standards.
http://www.isbn.org/