The founders Los Angeles-based GumGum, a startup which offers ad-supported, celebrity and entertainment photos for blogs and other web sites, has diverged into the online ad business, saying this week that it has launched a separate, advertising service called Bedrock. The firm said that Bedrock allows publishers to create ads and allow advertisers to bid on those ads, on a cost-per-click basis. Apparently, the new ad network was a result of difficulties GumGum had in monetizing its non, IAB-standard inventory through existing ad networks. Bedrock was founded by Ophir Tanz and Ari Mir, the founders of GumGum, and says it is supported by the same set of investors and advisors as GumGum, which include MySpace's Michael Jones, First Round Capital's Howard Morgan, GRP's Mark Suster, and Crosscut Ventures Brian Garrett.