You don't have to love rock & roll to love "Almost Famous," but it helps. From the early days when DJ Alan Freed first popularized the term to the pinnacle of rock in the 1970s, bands like Led Zeppelin and The Allman Brothers had become mythic figures that were worshipped by hardcore fans. "Rolling Stone" magazine had worldwide circulation and was considered a legitimate, respectable periodical that showcased these groups without compromising journalistic integrity. Interviews with...