You should do what your "professional gigger" did--basically it amounts to going up to the booker with a confident smile on your face and asking for the gig--it works, providing the booker actually has a gig available, and feels comfortable with you--but to make that happen, you need learn how sell yourself--and that doesn't come naturally to most people (especially folkies)--

It's best to learn at the foot of a master(like PG above), but they generally work alone, so the next best trick is to find a good book that teaches the process of one-on-one selling--with special emphasis on "cold-calling"--and study it closely(It won't likely be a music related book, but that's OK)--then just go--with persistance, things will fall into place--