Yes, it's frightening how much any one can find out about you. I recently got a e-mail forwarded to me by a local guy, originated from a man in Germany who said his 90 year old mother would like to find out how my wife and her sister are doing. Then he proceeded to list the family tree on that side of the family and he had every detail right on- even where my wife went to college and what year she graduated. He knew all the right names and relationships going back a hundred years! Since he has my address too, I wonder why he wouldn't contact us directly. I have now had two strangers in the area call me to tell me this guy is looking for us and requesting I reply to him.
No, I'm not going to reply. We don't know those people anyway, what's the point? Or maybe it's a scam of some sort.
I suspect all those genealogy programs on the internet are fueling this kind of activity and revealing all this personal info.
Be careful out there!