Constantine Maroulis, the “American Idol” alum who currently toplines the Broadway tuner “Rock of Ages,” will hit the road with the show’s touring production, launching in September in Chicago.Tour will be the second North American offshoot of the musical, which just began perfs of a Canuck production in Toronto. An Aussie incarnation will bow in Melbourne in April 2011, and a New Line Cinema feature adaptation also is due next year. Maroulis appeared in the Off Broadway staging of hair-metal jukebox musical “Rock” prior to its Main Stem engagement. He plays a wannabe rock star trying to make it in 1980s Los Angeles. After kicking off in Chicago Sept. 21, tour will play Boston; Louisville, Ky.; Seattle; Washington, D.C.; Fort Lauderdale, Fla.; and L.A., among other stops.