This link will take you to a state website. School corp sites are listed. Most school corp sites have info regarding vacancies.
http://ideanet.doe.state.in.us/htmls/k12.html (broken link)
You will also find info here on the licensing requirements--if your spouse does not already have an IN license.
The experiences of myself and a couple of family members in finding teaching employment in IN has been discouraging. Competition is stiff, and it helps to know the right people. A long time ago I looked for a job in Lake County. Never did get one there. The day I started at a private high school in IL I received a call from the Gary school corp to start the next day--no interview, nothing. Needless to say I did not take the job.
A few years after that a cousin looked for a job in Lake County--it took her a couple of years of subbing before she found a permanant position.
Just a couple of years ago my SIL--new graduate, looked for employment in Indy area. She became a permanant sub for a year. She would have received a job the following year except she and my brother moved to Tennessee. She found a job quickly and is happily finishing up her first year.
I hate to be so discouraging about this, but the fact is that IN public schools generally hire the cheapest teachers possible. This means people like your wife, with experience, or people like myself, with a masters degree, end up frustrated and jobless. It's one of the few professions where experience and education count against you when looking for employment. That's not to say there are not exceptions, but there are lots of new grads out there looking for jobs. An exception might be if your wife could/would teach special education.
Your wife might consider looking into the numerous Catholic schools in the area. (you don't have to be Catholic to teach there!) It could just be my experience, but they tend to hire more experienced teachers than public schools.