Some interesting links:
Jack Russell Terrier Club of America(JRTCA) - Go-To-Ground
Jack Russell Terrier Club of America(JRTCA) - Agility
The North American Dog Agility Council (NADAC)
The American Kennel Club (AKC) Dog Agility
The American Kennel Club (AKC) Earthdog Trials
The American Kennel Club (AKC) Lure Coursing
Dog Search Information - Worldwide dog directory.
Equine Barrel Racing