Hi,

I've been to japan a bunch of times (my wife is from there).

A good day trip might be to Omiya. It's generally the first train stop west of Tokyo. Mabye 30 min on the train. It's famous for Bonsai. I'm a bonsai fanatic and went there last year. It's a very easy day trip. Omiya is nothing special - a big city connected to Tokyo. However the bonsai village is pretty, with about a dozen bonsai growers / nurseries within walking distance of each other. If you go, I'd suggest taking a cab from the station to the bonsai village. Once in the village, there are street maps pointing out where the various bonsai places are.

Enjoy the trip!

Here's a 15 second video clip I made of a nursery in Omiya:

http://www.youtube.com/watch?v=ySHgBbR8lQY

P.S. Japan is very safe, even for women. Much safer than North America.

Here is a link that might be useful: Omiya Bonsai Village