I was also going to suggest, if the urge is there, to send the note to the school she worked at. Often times, retired teachers stay connected with their colleagues. Someone is likely to know who she is and may forward your note to her.. without creeping her out by searching for her house address.

I've run into 4 of my previous elementary/high school teachers. I made contact. I let them know who I was. The elementary teachers knew my family's story so they remembered me. Occassionally, I have coffee with one of them, as we frequent the same shop.

She may also be on Facebook?