Look at C/V bikes, mostly in Europe though. There was a 20" Bianchi on E-Bay recently, they do pop up from time to time. Check this thread for more info:
http://www.bikeforums.net/showthread...nior-roadbikes
Here's my daughters 22" Olmo:
http://www.bikeforums.net/showthread...o-finds-a-home
Originally Posted by
Andycapp