Shel Silverstein was one of those rare "multi-threat" artists -- composer, singer, cartoonist, illustrator, author -- with popular successes in all of those areas. Born in Chicago in 1930, Sheldon Alan Silverstein first attracted notice during his army service, in Japan and Korea, when he became a cartoonist for the U.S. Army publication Stars & Stripes. After returning to civilian life, he made a part of his living selling hot dogs at Chicago's two ballparks, and, according to a 1961 publisher's biography, set a record for the number of hot dogs sold at Thursday night games. He also began drawing cartoons for magazines such as Look, Sports Illustrated, and This Week, but it was when he joined Playboy magazine in mid-'50s that his name started getting known nationally. The magazine was then on the cutting edge of popular culture, and Silverstein's cartoons, which appeared in every issue from 1957 through the mid-'70s, with their satirical and provocative content, were some of the sharpest work in there. During the late '50s, Silverstein also began exploring other areas of creativity, including writing and music. He recorded an LP, Hairy Jazz, for Elektra Records, which featured two original songs as well as his interpretations, as a singer, of a brace of jazz standards. It was the first of a dozen albums that Silverstein would cut in the course of an active career of more than two decades in music, cutting across all genres -- his next album, Inside Folk Songs, was a sharply comedic look at the early-'60s folk music boom and all of its attendant absurdities, which included the original version of "The Unicorn Song," and he followed that up with a trio of LPs for Chess Records' progressive label, Cadet Records. During this period, apart from his work as a magazine...