Regarded in show business circles as one of the most versatile comedic entertainers, Steve Landesberg stepped on stage for the first time to perform at an open audition Bill Cosby was conducting for NBC's "The Tonight Show" at NYC's Bitter End. Soon after, he was working at the Improv with other young comics like David Brenner, Jimmy Walker and a young lady named Bette Midler. A stint with an improvisational comedy group called the New York Stickball Team preceded his first appearance as a TV regular on "Dean Martin Presents The Bobby Darin Amusement Company" (NBC, 1972). His first regular