Fred Lowery

Without a doubt, one of the best whistling albums in my entire collection. The whistling genre doesn't always get its due. (This record should won the Grammy for Best Whistling Album in 1967. Fred was robbed.) 

By the way, if you say "Professional whistler" real fast, it sounds a lot like "professional wrestler."

From his bio:

Fred Lowery was the most successful professional whistler of the 1940s and 1950s...Lowery's place among whistlers is rather like that of Art Tatum's among pianists. Fats Waller is reputed to have said one night when he spotted Tatum in his audience, "God is in the house."...His technique was so advanced and sophisticated that there really was no comparison..."People sometimes ask me what attributes make a great whistler," he once wrote. "Well, I think they're really just the same as for any other musician. He needs musical sense--good phrasing, good timing, good improvisational instincts--and mastery over his instrument, which in this case is his whistle."