In their letter, the ABA cited some concerning statistics regarding Amazon's share of current book markets: (wiseinkblog.com)
Certa Publishing helps authors not only publish and print quality books, but also push their books into the appropriate markets, providing authors with the most current book marketing opportunities available. (christianpublishers.net)
Inside Current Book Marketing, Review, & Promotion Sites for Indie Authors, there are categorized lists of over 300 links and time - saving information for indie authors to market and promote their books through: (cottaquilla.com)