I've lived near some Amish and have personally known a few of them.
What you see on television and popular media doesn't really capture an accurate portrait of them IMHO. For instance, most of the Amish aren't against modern technology, they are just slow adopters. Most want to make sure that anything new doesn't disrupt their way of life or interfere with their faith. Some of the Amish these days have cell phones and power tools. But of the ones that have cell phones they tend to have rules, like they only use the cell phones in a little phone booth away from the house to limit it's use.
Also, there's some disparity in the Amish community. Some of the Amish are fairly wealthy and own hundreds, sometimes thousands of acres of land. Most of this they rent/lease to other area farmers who farm the land with modern equipment. This alone can bring in hundreds of thousands to millions of dollars a year for the Amish. Of course, of the wealthy Amish, most of that is held by one guy which is the head of that family. These families can be pretty large with dozens of people, children, grandchildren, etc. Most of the children don't live nearly as well and have to obey the head of the family or they risk getting kicked out with nothing to their names.
They don't educate their children past about the 8th grade either. I don't know if this has anything to do with it, but a good number of the Amish kids I've met seemed to be a bit slow... this also works against the kids since it makes it harder for them to find work outside the community and be able to leave.
I know some of the shows make it seem like an idealistic life, living off the land and whatnot, but the reality isn't always so.
"Of all tyrannies, a tyranny exercised for the good of its victims may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated; but those who torment us for our own good will torment us without end, for they do so with the approval of their own conscience." -- C. S. Lewis