Gaits Without Gimmicks
The late Lee Ziegler has published one of the best books on gaited horses entitled Easy-Gaited Horses.  This book answers many questions about gaits and how to ride and train gaited pleasure horses.  Last time I checked it was available at Amazon.com.
www.leeziegler.com

YAHOO!
Yahoo has several discussion groups about gaited horses and Fox Trotters. Do a search and see which are a good fit for you.
www.yahoo.com