JETHRO'S PUPIL
TONY Snow is still a rock 'n' roll animal. The White House press secretary, a classic-rock freak, got a visit there on Wednesday from his old pal Ian Anderson, the zany, flute-playing frontman of Jethro Tull. "I've played with Ian on stage before," Snow told us. "I actually taught myself to play the flute by listening to Jethro Tull albums." Anderson will briefly turn classical when he plays with a chamber orchestra at Jazz at Lincoln Center on Oct. 5.