A guy did that to me last year. Told me he had seen me getting out of my car at my office in Mayfair. Was able to describe the car and place. Really creepy. Haven't used the front door since.
That scares me more than anything. A few years ago I had a stalker from Italy. He found my Facebook page, and he also found the Facebook page for a volunteer group that I head. He said he was going to meet me at the stables so I could take him for a ride.
For more than a brief moment I thought that he literally meant he was in Florida! I can't tell you how freaked out I was. I cried and sobbed and told my husband that I didn't want to leave the house. I even put my big pistol in my car whenever I went anywhere. I didn't go to the stables for weeks just thinking about it. He never left Italy, as far as I know, but it was many, many months before I logged on here again.
I don't know if I overreacted, but I was ready for anything. Intrusion in real life is very very scary.