I don't give up easily, but am giving it a rest for now.

In today's searching, this popped up:

http://www.directorypodcast.com/podcaster/archive.php?iid=7564

If you scroll to the bottom and work your way up, it starts at 2006 and includes such artists as: Amos Lee, Neil Young, The Little Willies, Dr. John, Sonya Kitchell (at 17), Dar Williams, Jeff Tweedy, Jay Bennett (after Wilco), Norah Jones, Sasha Dobson, Brandy Carlile, Ringo Starr, Phoenix, Warren Haynes, Ray Lamontagne, Decemberists, Grace Potter, etc. for a very long way.