I'm no expert, and I'm not quite sure about 'art song', but here are my thoughts:
1. "L'Homme Qui N'Avait pas de Maison," Lara Fabian and Jean-Felix Lalanne; (you didn't say only English songs need apply).
If art is helping you see more than the unattractive surface, then this song about a homeless man has to qualify as art.
Alternates, variations on a theme of love: (I'm a semi-rabid Lara fan)—Lara Fabian and Jean-Felix Lalanne, "Le Tour Du Monde," love just beginning; Carole Cournoyer/Kim Kuzma/Dave Pickell/Eddy Marnay, "Puisque c'est l'amour," the…