The Roots Harmonica 'broadcast' has been on Live365 in one form or another for four years, and it features all the Old Time Harmonica I can get my hands on, mixed with other acoustic styles. Jug Band, Country Blues, Cajun are all there, even some Irish, British Isles, and Quebecois.
Just about every source that's been mentioned so far has been or is being played: Deford Bailey, Dr. Humphrey Bate, Crook Brothers, David Rice, Mark Graham, Grant Dermody, Joel Bernstein, Doc Watson, Brendan Power, Noah Lewis, Jed Davenport, Otis Mote, Sonny Terry, Ernest V. Stoneman, Isom Fontenot, Bob Bovee, Mike Seeger, John Lozier - well you get the idea.