Oh yeah x2 on the "The Gathering", dunno how I missed that one in my earlier post.
Another big one I missed are the "Cowboy Junkies". Beautifully haunting vocals. Top picks would be "Lay It Down" and "Whites Off Earth Now!" and "Trinity Sessions"
I'd also add Nancy Sinatra to my list, one of my favourite classics.
Here are a few more :
Jennifer Warnes - Famous Blue Raincoat
Madonna - Something to Remember
Susan Wong - Close to You
Pink Martini - Sympathetique and Hang on Little Tomato
Martha Davis (from the Motels
Linda Ronstadt is absolutely awesome and does a variety of genres well
Ann Wilson (Heart)
Stevie Nicks, Christine McVie Fleetwood Mac
Rindy Ross (Quarterflash)
Natalie Merchant (solo and 10,000 Maniacs)
Deborah Harry (Blondie)
Yoko (just throwing this in to make sure you're paying attention- yuck!)