I am a bit late coming to this post but I thought I would mention: Harrisonburg has Mennonites, not Amish and while they run a farmer's market nearby, it isn't like PA, where you can go on a farm and observe their lives. They live quietly and unobtrusively.

A better bet for "farm life" is the Frontier Culture Museum in Staunton, VA. I have this weird desire to try milking a cow and my husband actually called all the dairy farms in our area to find one for me to try--no luck, they are all rather industrial. But the Frontier culture museum sometimes lets visitors try their hand at milking at the end of the tour (I haven't actually been yet, though).