I don't recall the name since his account got banned and the post removed, but he had quite a lot of IPs from people.
Ok, seriously speaking, if this is really happening, immediately contact Dyna or Cyp, and they can help to figure it out. If things get bad on your side, do call the police to deal with it, if it's serious. In future, try not to release that much personal information when contacting someone in-game.
Support for @Andrewswj 's suggestion. Aside from that, I suggest downloading some sort of recording software, such as Bandicam, so you are able to obtain evidence if something like this happens to you in the future. Also, here are a few links you may find useful: http://www.mineverse.com/forums/report-a-player.86/ ^Reporting a Player^ http://www.mineverse.com/threads/read-forum-report-template-forum-report-information.33868/ ^Required Report Template^ http://www.mineverse.com/report/ ^Report Rules and Options^
Take screen shots or record of video of these things, report it on forums. He should be banned if you have the right evidence