Well, I don't know about a formal list, but....I subscribe to: Dulcimer Players News, which gives tab and dots for both hammer and fretted dulcimer. Guild of American Luthiers, good advice on mantainance of instruments, as well as building. Sing Out, good for tunes, and leads to other publications. I'm particularly fond of specialty magazines, so perhaps I am biased. For organizations: Mudcat, which you can donate either money or labor to, and Victory Music, which is an organization in Washington State, and helps out aucostic musicians.