A moderator or guide for new users

I have seen it in other forums. To help newbies a special kind of moderator.

Could be
Newbie Adviser

 

I'm not sure, I think some people find the term "newbie" a bit insulting? (then again, some folks will find anything insulting, so we can't worry too much).

That said, how about "welcoming committee". Members of that group could simply have that in their sig, or under their avatar.

 

Just call him advisor for new members or just mentor.