What else sounds like Norah Jones?
No one else you'd find on any pop radio station today.
<cringe>
Norah Jones is nothing new--she's successfully ressurecting a very old genre called Vocal Jazz. Her contemporaries are mostly really old fogies/dead... but we're talking jazz icons here.
Ella Fitzgerald
Dinah Washington
Nina Simone
Billie Holliday
Etta James
Julie London
Nancy Wilson
Sarah Vaughan
Diane Reeves
Shirley Horn
Some newer artists in the same vein:
Diana Krall
Cassandra Wilson
Edit: Those are just the women---there were men jazz vocalists as well, but I assume you were looking for the soothing female voices, as opposed to, say Louis Armstrong's rasp.
Enjoy! I must say it's nice to hear something completely different on the radio than the same old pop, numetal, "alternative" rock schlock.
l2c