NovelRank - Amazon Sales Rank Tracker
NovelRank is a completely free website for tracking books or other product's Amazon Sales Rank on Amazon.com, Amazon.co.uk, Amazon.ca, Amazon.fr, Amazon.de (Germany), Amazon.co.jp (Japan), Amazon.cn (China),Amazon.it (Italy), and Amazon.es (Spain). NovelRank is the best free resource for self-promoting authors to track their print and ebook sales and Sales Rank on Amazon with charting, RSS feeds, and real-time data.
For non-book tracking or large volumes, use NovelRank Enterprise Edition sales rank software.
"It's really, really cool... and robust. So much better than anything else out there."