Diana Krall, Norah Jones, Jane Monheit....?

Well, within the last 6 months I've found that I have a love for female Jazz singers. It started with Diana Krall and then Norah Jones and as of the last couple of weeks, Jane Monheit. Any recommendations on other great female jazz singers? How about male jazz artists?

It's always fun to explore a new genre and I love what I hear so far. :-)

She'd be horrified to be mentioned in the same breath as the three above, but Patricia Barber is a true great, in my view.
Glad to see someone mention Tierney Sutton. You have some great suggestions - BUT to anyone who hasn't heard this following woman - you owe it to yourself to at least give her a listen - Jackie Allen!
PS - for male jazz singers, try

Philip Manuel

Jamie Cullum (really)

Kevin Mahogany

Steve Tyrell (already mentioned)

Michael Bubble

Johnny Hartman

Kurt Elling

Just to name a few