Hello Dave:
There certainly are some recordings of source singers on the site - Billy Buckingham, Lem Hayward, Dick Parsons, Harry Aldrich, Betty Aldridge, Harry Boucher, the Stevens family, plus several links through to Roy Palmer's and Nick & Mally Dow's collecting on the British Library Sound Archive website. Try the search on the home page and you will find them, or go to the respective song and follow the links to Archive recording.

Tradsinger