(HOUSATONIC, Mass.) – John Gorka, Christine Lavin, Dan Bern, Bill Staines, Rory Block, Jonathan Edwards, Barry McGuire, Vance Gilbert, and, of course, Arlo Guthrie, are just a few of those slated to perform in the 2011 Summer Troubadour Series at the Guthrie Center, located at the Old Trinity Church where Alice of Alice’s Restaurant fame…