We have an IRC if you need someone, but it's a day old and still taking off, so...
Really, you have two options if there are no admins on. Go to the ingame irc and type !Guard, to call a guard, or take screenshots and videos of the griefer in action, take it to the reports thread, and laugh at their master server ban.
Visit the Beginner's Box
Introduce yourself, read some of the ins and outs of the community, access to useful links and information.
Comments on Profile Post by Dask