Mountain Bike Racing:

Wisconsin Off Road Series

Wisconsin Endurance Mountain Bike Series

Other Cycling:

Bicycle Federation of Wisconsin

WI USCF Racing

Wisport

Mountain Bike Review

Cyclocross

Useful Training Utilities:

GMap Pedometer for mapping out a bike route, with mileage

Bike Map of Dane County  and  Legend of Map

Wednesday Night Bike Rides

Other:

Chainsmokers Mountain Bike Team

Re+New Vintage