There are two volleyball associations that provide services for coaches and players: AVCA and USAV.
American Volleyball Coaches Association (AVCA)
The organization provides leaderhip, advocacy, and professional development for its member coaches. AVCA is recognized for the following:
USA Volleyball
USAV is the National Governing Body (NGB) for the sport of volleyball in the United States. Its mission is to lead, serve, and grow all areas of the sport of volleyball (beach, indoor and sitting). As part of that effort it manages the high performance programs for the United States.
One of those events is the High Performance Coaches Clinic at the USA Olympic Training Center in Colorado Springs. The event features top collegiate players and newcomers to the national team, along with their coaches.
This sequence of photos shows Carly Wopat demonstrating a hitting drill at a recent HP Clinic.
The following pdf files illustrate skills demonstrated by other athletes at recent clinics.