Salesforce.com has acquired a tiny company that created an add-on to its hosted services for purchasing and managing Google-driven Web advertising campaigns. The acquisition brings the operations of Kieden, a four-person operation with 45 customers, to Salesforce.com. Financial terms were not disclosed.

Salesforce.com CEO Marc Benioff and Kieden co-founder Kraig Swensrud detailed the purchase at a press and customer event in Boston on Monday. Swensrud said that the service, called Salesforce for Google AdWords, lets people launch a Google AdWords advertising campaign from a Salesforce.com application. It will cost $300 per company per month. The service allows marketing and advertising managers to analyze ongoing campaigns by viewing which people who click on Google AdWords keywords become sales leads. It compiles information, such the amount of sales resulting from Google AdWord clicks and presents it in charts and a dashboard-like interface.

“The problem…is trying to get information from Google AdWords to knowing who the customer is can be kind of a difficult thing,” Benioff said. “You tend to lose the link between CRM (customer relationship management) and Google ads.”

Former Kieden employees built the integration between Salesforce.com applications and Google’s ad-serving system using AppExchange, the development environment of Salesforce.com.