Bookstores Online 
ABI Forms and information
Bartlett's Familiar Quotations
http://www.cc.columbia.edu/acis/bartleby/bartlett/

Amazon.com
http://www.amazon.com/

Barnes & Noble
http://www.barnesandnoble.com/

Book Industry Study Group
http://www.bisg.org/
Bar code information and more

Book Wholesalers
Baker & Taylor
http://www.btol.com/

BookZone
http://www.bookzone.com/
A treasure of book information

Borders
http://www.borders.com/

Ingram Book Group
http://www.ingrambook.com/ http://www.ingram.com/