How easy is it to stalk somebody on the internet?

I've known people that have said that it's surprisingly easy to stalk someone across the internet with just a little info. I fear this may be going on with me. Has anyone out there ever had someone send your girlfriend a malicious message on myspace or elsewhere? Ever stalked someone yourself?

How easy is it to stalk somebody on the internet?
I went thorugh a stalker phase in highschool and I'm telling you it is HARD to stalk someone. The main thing is whether or not they make themselves available to you. The guy that I was stalking, posted his entire family genealogy... I know everybody that is related to him down to the last 12 generations and all his 4th degree cousins and I have his mother's resume, and the place where his brother works, and the college that he goes to, and his home phone number and address... and all by discovering his last name through his facebook account.
Reply:no thats wrong..
Reply:hey...first of all thats wrong..you should not do that to somebody it really hurts the privacy factor of the person...
Reply:I had a stalker who did it in real life and also over the internet, cell phone etc. Save EVERYTHING you see. He ended up incriminating himself and I was able to get him arrested and put in jail. Again, save EVERYTHING. I have a folder 3 inches thick of stuff.....
Reply:No I haven't I have bee stalked at home though I met my husband through an old friend and after we started dating she would always be evrywhere we would go she would even walk in the door when I still lived with my mom and dad she left town for a couple years and she works at walmart and she was in every dept I went in after she first saw me can't avoid walmart only store cheap enough in our town