Eric Endres of Buffalo gets no 76-trombone salute for his fan site's design, but Meredith Willson's wit and whip-smart lyrics are attraction enough: ''I cheer/I rave/For the virtue I'm too late to save/The sadder but wiser girl for me!'' Endres also tracks ''The Music Man'''s Broadway-bound revival and its rumored TV adaptation by Disney. The verdict: unexciting but practical with a capital ''P'' and that rhymes with...