The most important part of picking up unlisted traditional material is simply to be where the people who know it are. I once picked up an unlisted couplet in the middle of the afternoon in Brooklyn on Labor Day Weekend from an old guy who used to be a whaler in the Caribbean. Once you have the basic material, you have to be persistent in filling in the blanks, even if that means you have to go on collecting trips to exotic places. Isn't that rough? Of course, you may find yourself outward bound on an unplanned voyage, but that is the definition of adventure.