Hi, We have done something similar in the past, what kind of personality profile did you build? , I would highly recommend to base your investigation in a social network analysis. http://www.ire.org/sna/. Since it will allow you to widen your search-range (pretty useful when you hit the wall..  ) Our suspect was a low profile user, so It took us some “tunning” on a couple of open-source webcrawlers, and some googling to track him down. (at the end we were able to figure out it was a team of users), we even setup a couple of alerts (both on yahoo, and google) to keep us updated on their moves. You should try something like http://www.jibble.org/piespy/ , see what you can get from there.
Keep us updated!
