Based on my favorites, what are some lesser known bands/singers that I should check out?

Tori Amos
Kate Bush
Bjork
Beck
St. Vincent
Andrew Bird
Joni Mitchell
Tom Waits
Elvis Costello
Randy Newman
Arcade Fire
Spoon
Wilco
Arctic Monkeys
The White Stripes
Dave Matthews Band

Also feel free to recommend music to other people. Thanks!