After months of speculation about a Google acquisition of Aardvark, the deal is finally done, according to co-founder and CTO Damon Horowitz.

Google has acquired the social search engine startup for a reported price tag of $50 million. Because Aardvark was founded by ex-Googlers, the acquisition marks a return home for the young entrepreneurs.

Aardvark is a question-and-answer service that lets people find information by asking the trusted community of people around them, which includes friends and friends of friends. You can ask a question about whatever you want, and the service will try to match the query up with another user, who has expertise on it. Aardvark connects people to questions using the interests they list on their Facebook profile or share with the site.

Google is acquiring Aardvark at a time when the paradigm for finding information online is shifting. It’s not necessarily that search is diminishing in power. It’s that sites like Facebook and Twitter are enabling people to find out information from their friends. Every bit of information a user finds out from an acquaintance could be one search lost by Google.

Aardvark might integrate well with Google Buzz, or its local listings. It would be particularly helpful for business pages, since it would allow curious customers to ask specific questions to business owners or other customers.

The San Francisco-based company opened to the public in October of last year, but it’s been around since 2007. It raised about $6 million in first round funding from August Capital and Baseline Ventures.