Thanks to both of you for the responses. This is all very helpful.
Going to grad school to study this subject is what I really want to do. I think it would be fulfilling for me on a number of levels. After years of working jobs I hate and struggling to get through my BA, I want that intellectual satisfaction. Right now, I'm leaning in this direction even though I am afraid of the risks. Teaching secondary school is my second choice, as I said, but not my dream. Another close friend is a middle school teacher, and while she likes the stability, she says that she spends about 70% of each class period trying to get the students to sit down and be quiet. She taught reading one year and said that it was a miserable experience because the kids all hated to read; and when they did read, they read sports magazines. It's an admirable job, but not something I expect will make me happy beyond the steady paycheck and vacation time.
Wyatt's Torch, thanks for your input. It's good to know that I'm not the only 35-year-old out there who is about to begin this process. By the time I actually begin a program next fall, I'll be 36. I feel old compared to so many who are about to go into grad school, but I know that I would not have been prepared for this in any way at the age of 22, or really at any time in my twenties. I will pm you.
And I guess I should have mentioned that becoming a professor is not necessarily the ultimate goal for me. I would be happy to find a career in another line of work if it involves the interests that are most important to me. Working for a museum or some other organization involved in this subject would be fine. I just really love it. And that's part of why, aside from the probable rejections I would get, I am not planning to apply to any PhD programs right away. I want to start with an MA to see where this can take me.
So, I'm going to look through that Cambridge Companion and see where all of these professors are these days. And I guess that leads me to another question. I've never written to professors at other institutions with these kinds of questions, but as you say, I need to reach out to them. Any suggestions about what exactly I should be asking? I do feel a bit intimidated approaching them, but I know I need to. I'm not exactly sure where to begin.