SERPStream is a 100% free SEO tool. Members can keep track of their site's Search Engine Results Page position with updates as frequent as a dozen times a day. SERPStream have a great newsletter, sends email alerts, and have a state of the art keyword rank tracking dashboard.
Rank Tracker - Rank Tracker is an SEO tool for tracking and improving keyword rankings across multiple websites and search engines.
Serpstat - Search analytics, Rank tracking, Backlink analysis and Site Audit tool.
SEMRush - All-in-one Marketing Toolkit for digital marketing professionals.
SEO PowerSuite - Get all SEO tools in one pack - download free edition of SEO PowerSuite and get top 10 rankings for your site on Google and other search engines!
Pro Rank Tracker - Rank tracking & reporting software solution
SEOmator - SEO website analysis & audit tool