Rap music from New York and Los Angeles once ruled the charts, but nowadays the southern sound thoroughly dominates the radio, Billboard, and MTV. Coastal artists like Wu-Tang Clan, Nas, and Ice-T call southern rap "garbage," but they're probably just jealous, as artists like Lil Wayne and T.I. still move millions of copies, and OutKast has the bestselling rap album of all time.In Dirty South, author Ben Westhoff investigates the southern...