Hi Moat,
Being "accredited" by the State has nothing to do with whether it is a good school--at least in the sense of whether you will learn what you need to learn to be able to get and keep an MT position. The states are looking for different criteria.
My suggestion would be to go to
www.ahdionling.org and choose one of their approved schools. These schools have been reviewed by this organization's very knowledgeable MTs and have passed the minimum standards to be approved. There are differences even among these schools, so research carefully. Find out what you get for your money--some schools furnish equipment and books as part of their tuition and some do not.
Also, do not go with a school where you are transcribing with tapes--they are almost completely obsolete (example: I was at an MT symposium and I took a poll--this was 2009--and asked how many people used tapes to transcribe. Out of 50 people, 3 raised their hands). I would assume that all of the AHDI-approved schools would require that you use the AHDI Book of Style, 3rd edition. This is a must for MTs.
There are other schools that offer editing among the AHDI-approved schools.
As far as whether this is a good time to get into the field---wages have dropped dramatically in the past 5 years. It is also hard for newbies to get work because many services want people with at least 2 years of experience. You are paid by the line and the line rates these days are the same as they were 15 years ago--around 7-8 cents per line. As you get more experience you can make more money and a small percentage make a decent wage, but the majority of MTs do not. There is a lot of pressure to make a certain line count. In addition, with many of the national services you are usually given multiple accounts and so it is difficult (especially for a newbie) to get any traction to get your line count up when you are constantly being given different dictators on a daily basis. Some services are better about that than others.
Anyone who has come into the field in the last 5 years or so doesn't remember the "gravy" days when you actually got paid a decent salary commensurate with what you were required to know, but I could now work at Wal-Mart and make about the same.
It was nice to be able to stay home with my children, though, so if you are willing to make less than you should be to do this job in order to stay home with them and your spouse has good benefits, you might make out okay. The national services have insurance but it is very expensive.
Not trying to be a downer, just a realist.