That's so weird... I lived near the Amana Colonies (in Grinnell, and then Iowa City) for 15 years, and always assumed they were Amish. Love that place!
The colonies are definitely a good place to visit. Tho' you have to travel a bit further and look carefully to begin to pierce the veil they put up for outsiders. Even then, you are still an outsider.
As for the Amish, they're here in NY. Not what you would think. A good start is Amish Society, by Hostetler.