Society of Indexers: http://www.socind.demon.co.uk/

Macrex Indexing Services: http://www.macrex.com

Publishing News Online: http://www.publishingnews.co.uk/

Library of Congress: http://lcweb.loc.gov/homepage/lchp.html

British Mensa Ltd: http://www.mensa.org.uk

The Bookseller.com: http://www.thebookseller.com/

Symantec Ltd: http://www.symantec.com/