In the New York City area there is a group call PLTG (Professional Legal Trainers Group)PLTG It's membership is open to all legal trainers and vendors.
Does anyone know of a networking group for Legal Training Managers and Directors?
Try ILTA - the International Legal Technology Association. It's not for just for training - it's for IT people in general - but a lot of trainers and training managers are part of it. They have various discussion boards dedicated to MS Office, user support, etc. and there are local chapters in many big cities. Here's their website: