Having been through tech school in the past I can say a few things. It gives you a foundation for on the job training. You will not be ready to be a on your own tech no matter what school you go to, and most likely not be hired as one. I worked in shops went to tech school and continued working as I was in school. Tech school also only offers what you make of it and your instructor is willing to teach. My best advice is to get a job in a shop part time, and your going to push brooms, clean toilets, take out trash. Show good work ethic and a willingness to learn while at that job. While doing so take business classes at a community college ect. maybe even a few tech courses.
You will never learn it all in school in this business, and having the education on the business end allows you more opportunity to move into the operation/management side of things with greater ease later on. Washtenaw Community College as mentioned above is a great place to look into. They offer a good technical program, and offer the general college courses that transfer all in the same place *much more affordable also*. But as I said this is what I can offer from my experience. Having gone through this road and a current tech (and still learning) its all about the drive of the individual to make it happen.