Greg, I have liked Edmundo Ros from way back! Chocolate Whiskey and Vanilla Gin (I buy horse with a V shaped back, once was a winner on a Trinidad track. Now he's boney, old and thin, one more race he can surely win.)

I'll only list non-folk secret pleasures, as opposed to unhip folk singers that some seem to disregard or take lightly. You know some of the ones I am referring to. I figure to be included here, a performer has to be a good long ways off from Folk/ Old Time/ Blues/ Bluegrass/ Related Music.

Jewel Kilcher (not everything, but enough to include, same for some of the others)
Any number of Australian Country Music Singers ~~ Sara Storer, a bunch of Kernaghans , Schneiders, Dead Ringers, etc.
Heidi Hauge
Real oldies like Henry Burr, Ada Jones, Billy Murray . . .
Clyde McPhatter
Pink Martini
The Slaptones
Miss Mary Ann and her Ragtime Ramblers/ Ranch Girls
Annette Hanshaw
Frank Chacksfield
Bert Kaempfert
Spike Jones
Many others, this is just a small sampling