Back in March, 2006 newspaper publishers The Tribune Co., Gannett and KnightRidder (now McClatchy) acquired 75% of news aggregation and community site Topix.net. But with the exception of a minor placement of a “contextually relevant news” box on content pages of some of those sites, the newspaper owners haven’t done very much with Topix.

Now, however, Tribune has struck a deal that has Topix providing content and a back-end platform for general merchandise classifieds on their newspaper sites. (Tribune is currently trying to sell itself.) Consumers will be able to upload images and text descriptions, starting on the Baltimore Sun site, but extending to all of Tribune’s 11 other newspaper sites by May. The ads will also be distributed across Topix.net’s thousands of local news pages.

The ads are free, which is the nationwide trend with private party merchandise. This deal does not extend to cars, jobs or real estate, which have resisted the free trend to varying degrees. There will apparently be a paid category (offering premium placement) as well, which is the basis for a revenue share between Topix and Tribune.

Topix has offered free classifieds listings on its own site since June of 2006. A few newspaper sites have also begun to use Topix to power comments and community on their sites as well.

Recently, Topix newspaper owners invested an additional $15 million in the site. According to Hitwise, Topix is a “top 25″ news site.

While there is still considerably more that the newspapers can do with an asset like Topix, this is a start.

Related Topics: Search Engines: News Search Engines

About The Author: Greg Sterling is a Contributing Editor at Search Engine Land. He writes a personal blog Screenwerk, about SoLoMo issues and connecting the dots between online and offline. He also posts at Internet2Go, which is focused on the mobile Internet. Follow him @gsterling. See more articles by Greg Sterling