Just about every artist I love today was heard originally on one of these
compilations:
Big Times in a Small Town (Marth's Vineyard Singer Songwriter Retreat)
Follow That Road (2nd annual Retreat)
When October Goes
On a Winter's Night
Laugh Tracks
A bunch of other good ones:
Shelter (The Best of Contemporary Singer Songwriters)
The Best of Folk Music (Putamayo does a lot of these kinds of comp.)
Ben & Jerry's Newport Folk, Kerrville Folk, Rocky Mt. Folks
Mountain Stage presents...(lots of volumes)
Hope you find what you're looking for.
Joanna