Wappalyzer - Wappalyzer is a technology profilers and leads data provider. Create lists of websites and contacts that use certain technologies.
SalesOptimize - Selling to online retailers? Revolutionary sales lead generation search engine driven by deep web analytics
BuiltWith - Find out the technology behind websites
Elucify - A completely free software tool that uses crowdsourced data to find business email addresses
SiteRecipe - Siterecipe.com is a technlogy lookup website as well as a lead generation tool ,the website help you create reports on web technologies and there use acrose the internet.
Nexsales - B2B Demand Generation