That kingdom hearts song is good.
Well, there are ALOT of female fronted bands out there, I can't think of any bands that you guys might like off the top of my head
but a couple metal bands would be
Nightwish (power metal)
Midnattsol
Elis
You might of heard of
Flyleaf or Evanescence but I don't really like them as much
OH yeah, theres a couple female folk/acoustic artists that are really good, Emilianna Torrini, Jana Hunter, and Diane Cluck.
Google some sometime!!! (some might be really underground and hard to find though)