arent all singers natural beauties??? the only person i can think of this isnt very beautiful is susan boyle, but most people dont want to look at someone like that unless they are singing a ballad or something more classical. pop music is greatly influenced by image, so pretty much anyone who is a well known singer is actually quite good looking as well.
the first one that comes to my mind is 'Jordin Sparks', not because I love her, but isn't she natural? She's so gorgeous! Another one is Lady Gaga, idk, but I really find her awesome!
Leona Lewis too, she's so hot! and also Jessie James!