What the site does is aid harrassment. Just because names and phone numbers are public domain, it's illegal to post them for the purpose of harrassment, especially when that harrassment does occur en masse. In addition, the site and forums had directions on how to properly harrass someone and how to use free programs to avoid detection and possible prosecution.
There was most likely no legal action taken because sites like this are so easily taken down, plus the threat of police is usually enough to scare most people away. If PB did get his site back up, especially if it were hosted overseas, you'd better believe they'd eventually come after him (if they could get to him). He's already had his warning; any judge would see that as knowledge that the site shouldn't be up in the first place.