TargetSpot, the CBS-funded online streaming media ad targeting firm, has acquired Ronning Lipset Radio, an online radio advertising representation firm, and claims it is the largest online radio advertising network. The price was not disclosed, reports NYT. Update: The official release is out.

TargetSpot’s service allows anyone to buy audio and visual ad space on its website, to be played on the 600 online radio sites in its network. Ronning Lipset has been selling ads for Internet radio companies like Yahoo, Live365, AOL and CBS.

Earlier this year TargetSpot was tapped to provide the end-to-end marketplace for advertisers for the merged *CBS* Radio-AOL internet radio network. NYC-based TargetSpot has raised two rounds of funding previously, from Bain Capital Ventures, Union Square Ventures, CBS (NYSE: CBS) Radio and web animation company Oddcast, among others.

Update: The official announcement is out. The combined company will represent more than 1,000 stations for 50-plus radio groups and web properties. Eric Ronning and Andy Lipset and their team join TargetSpot; the Ronning Lipset co-founders will be co-presidents of sales.

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