What songs can you name that feature whistling in them? I'll make this a wee bit harder. I'll get rid of two most obvious ones first: "Winchester Cathedral" and "Sittin' On the Dock Of The Bay".
"Can't Smile Without You," Barry Manilow "The Stranger," Billy Joel "Two of Us," The Beatles "I Keep Mine Hidden," The Smiths
Jealous Guy Nobody Loves You (When you're down and out) John Lennon Sweet Georgia Brown - Brother Bones
Yep, the instrumental version of the Andy Griffith Show theme has whistling. BTW, this song does have lyrics and the song is actually called "The Fishin' Hole."