NASHVILLE isn't nicknamed Music City for nothing. Singers, songwriters and pickers -- not to mention their toe-tapping admirers -- have been pouring into the Tennessee capital for decades. Yes, the city's rhinestone-studded past still glimmers, especially downtown, where you'll find Hatch Show Print, the legendary poster shop, Ryman Auditorium, home to the original Grand Ole Opry stage, and a slew of honky-tonk joints.