When Bob Seger turned 30 years old in May 1975, he found himself caught between nostalgia and a dream. Mr. Seger pined for his high-school years, cruising around in fast cars with friends in Ann Arbor, Mich. But he also yearned for the rock stardom that had eluded him after 14 years of performing and eight sluggish-selling studio albums. For his ninth L…