Appleseed Shoots are great fun!
Kids under 21 shoot FREE as well as anyone that is in the military (active, reserve, guard).
These are shooting clinics, not competitions.
They are a "bring what you have", event, no special equipment required. You will find it easier to shoot with a mag fed semi-auto, but bolt guns are often used with great accuracy and proficiency as well.
Here is the official web site.
http://www.appleseedinfo.org
Here is an unofficial web site that does a great job of preparing you for an Appleseed and giving you information about what to expect.
http://appleseedshoot.blogspot.com/
Great fun and information!