I have just stumbled across this online guide book which I believe is of great value to any of us selling farm products (plant/animal).
It is published by the Drake Agricultural Law Center, (Drake University, Des Moines, IA), and can be read in its entirety online for free. It is the 2nd edition (latest).
The Legal Guide for Direct Farm Marketing
Willie Smits: Village Based Permaculture Approaches in Indonesia (video)