Search marketing and analytics software firm Enquisite has closed an $8 million second round of funding. New investors Castile Ventures and Formative Ventures led the round; previous backers The Entrepreneurs’ Fund III and Retro Ventures also participated. The S.F.-based company has raised $11.2 million since its inception in 2006, and will use the new funds for product development, sales and marketing.

Search marketers can use Enquisite’s technology for keyword research and to measure the ROI of their campaigns; the software tracks stats including when and where the ads appear, and the number of clicks they generate. There are competitors of varying degrees like WebTrends and Lyris; Google, Yahoo and Microsoft also provide free campaign analytics programs for advertisers.