It is possible to join the Amish . The steps are written in the second paragraph below. They accept new arrivals, but it is very rare. "Can an outsider join the Amish church/community?"
"A local Amishman recently remarked, "You do not need to move here to adopt a lifestyle of simplicity and discipleship. You can begin wherever you are." Yes, it is possible for outsiders, through conversion and convincement, to join the Amish community, but we must quickly add that it seldom happens. First, the Amish do not evangelize and seek to add outsiders to their church. Second, outsiders would need to live among the Amish and demonstrate a genuine conversion experience and faith that results in a changed lifestyle. Third, it is extremely difficult for anyone who has not been raised without electricity, automobiles, and other modern conveniences to adjust to the austere lifestyle of the Amish. And to truly be a part of the Amish community one would need to learn the Pennsylvania Dutch dialect."
http://www.800padutch.com/atafaq.shtml
An "outsider" becoming a "successful" member of the Old Order Amish church is an extremely rare occurrence, but not impossible. However, it is extremely difficult, in the long term, for an "English?" person to give up modern accoutrements for the extreme discipline of the Old Order Amish. Such a conversion would include formal instruction in Amish beliefs and the German language as well as baptism -- not to mention almost impossible and significant lifestyle changes. I know of only two individuals from the outside world who have joined the Old Order Amish church and remain members in good standing today. Several (the Amish call them "seekers") have made the attempt to join, but have failed. However, the Amish are adopting non-Amish infants at an ever increasing rate.
http://www.holycrosslivonia.org/amish/q_and_a_no2.htm#no2
