Back in the summer of '69, Gap sold just Levi's, LPs, and tapes. 1969 was a long, long time ago. All growed up now, 3,000-plus location chain will hook you up with everything from bathing suits to bras, hoodies to hosiery. Bewildering array of jeans, but if you can master it, you just might find the perfect pair, at least for the few months before they wear out. Harlem claims its own outlet...