abebooks.com
Abebooks UK
Amazon.ca
Amazon.com
Amazon.co.uk
Amazon.de
Antiquarian Booksellers Association of America (ABAA)
Barnes & Noble
Blackwell's Bookshops
BookBaazar
BookBooters
BookCloseOuts.com
BOOKS ON TAPE® audiobooks
booksamillion
Books-for-Cooks.com
BookSense.com
ebay.ca
ebay.com
eBooks.com
eHarlequin.com.
ElephantBooks.com
nelsondirect.com
Pickabook.co.uk
Powell's
Proxis
World Book Store