** FILE ** Singer Robert Plant, left, and guitarist Jimmy Page, right, of the British rock band Led Zeppelin perform at the Live Aid concert at Philadelphia's J.F.K. Stadium in this file photo July 13, 1985. Led Zeppelin, one of the last major acts to resist digital distribution, are releasing their back catalog online. Songs including "Communication Breakdown," "Whole Lotta Love" and "Stairway to Heaven," will be available from online music stores Nov. 13. The band is due to release a two-CD retrospective, "Mothership," the same day. (AP Photo/Rusty Kennedy)