Seanan McGuire! (Filk musician and author, win win!)
Also, Mary Crowell and/or Play it with Moxie.
I do understand that filk isn’t really everyone’s schtick though. But I’m going to say Marc Gunn also.
I’d second lots that are already mentioned. Particularly if you got Beagle, or Gaiman, or Palmer, or or. Oh who am I kidding, I love everyone.