Please don't take the following as necessarily referring to people who have already posted in this thread...
But: I do believe that in a lot of cases the stalkee is partly to blame for allowing the situation to continue, rather than being firm in an effort to put an end to it. I've spoken (in person, not online) with several guys who have said something like "This guy wants to keep seeing me, but I really don't want to continue with the relationship." They don't know how to reject someone without being rude, they don't wish to be rude, so they just drop hints, which of course are never taken up by the other. Being rude is somtimes necessary - it should only be a last resort, but it should be available as an option if all else fails.
I've never been stalked in the threatening sense, but I have had a couple of guys who wanted more of my life than I was prepared to give. One in particular made a habit of calling on me around nid-morning on a weekday, when I couldn't claim I was tired and wanted an early night, and obviously it wasn't a day on which I was rostered to work, since I was home. The sex was good at first, but it got to be kind of the same thing each time and I didn't really feel attracted to him in any other way, so I began to find myself hoping he would not call. One day he telephoned to find out if i was in, and I took a deep breath and said "Yes, but I think we've done it to death, don't you?" He did ring once more, but I said I really didn't want to continue, and that was that.
Then there was the guy who knocked on my door in the middle of the night and presented me with a bunch of flowers - but that's a tale for another time.