This month Wicked Dungeon Masters will be offering live DM in game training during the NWCon4 event. http://www.NWCon4.info I will post details and time here when Scheduled (if they dont beat me to it.)
Sojourney: The Bloodstone Lands will be hosting a tips-n-tricks seminar for those who might be new to multi-player games, regardless of whether that might be on a persistent world or a run through some of the wonderful modules on the Vault.
On the other hand, if you want to know more about what goes on behind the scenes from a gamemaster's perspective or want to just meet and chat with other DMs in the game, then Sojourney is also hosting: