Big Sky Draft Horse Expo - http://www.drafthorseexpo.com/
Held every year in Deer Lodge, Montana and has a horse and mule show with racing and other activities. Dates and lodging details.
Rocky Mountain Horse Expo - http://www.rockymountainhorseexpo.com/
An expo dedicated to horses and equestrian. Includes ticket information and dates.
The Great Pocomoke Fair - http://www.thegreatpocomokefair.org/
Information and images from the fair that has a horse show as well as harness racing.