Celine Dion at one time.
Stevie nicks or amy lee
I had to really think . . . I guess it would have to be Kelly Clarkson. Her range of WHAT she can do is fantastic.
Hands down Sarah McLaughlin.
I like Hayley Williams of Paramore. That's one of my favorite bands and her voice is awesome :)
There are so many great ones, but I think I'd have to go with Ella Fitzgerald.
Varies all the time?