Labrador retrievers are exellent hunters. Beagles, I highley recommend beagles.
Beagle, Basset hound, Hound ---Another Answer--- Traditionally, a breed of dog called a "Foxhound" is used for hunting fox. There are two breeds...the English Foxhound and the American Foxhound....
The airedale.
Actually a lot of different breeds are used but the most common is various breeds of Hounds, such as the Black & Tan Hound.