Hamfests are like festivals or state fairs for amateur radio operators. They usually have a "flea market," where attendees can buy and sell used radio and related equipment and accessories. They may also feature manufacturers and vendors of new equipment, other exhibitors, seminars, and license examination sessions. Putting on a hamfest is a lot of work and there are always plenty of opportunties to volunteer to help.
The Raleigh Amateur Radio Society (RARS) puts on RARSfest at the NC State Fairgrounds each spring. We are always looking for volunteers to help out.
See the RARS homepage for a list of hamfests within a reasonable drive from the Raleigh-Durham-Chapel Hill triangle.