There's a handbook.

Joe Wilson and Lee Udall, Folk Festivals: A Handbook for Organization and Management (University of Tennessee Press, 1982, x+278 pp.)

Contents:
Part One
1. History, Concepts, Definitions
2. Administration
3. Programming
4. Publicity
5. Hospitality
6. Production
Part Two
7. Examples of Festivals
8. A Performer's Point of View
9. Samples of Festival Communications
Bibliography of Folklore in America by Charles L. Perdue, Jr.
Index

~Masato