Local groups are an effective way for system administrators in an area to share information.
There are now local groups in many parts of the United States, plus Australia and Canada, and everybody who's done it has found it worthwhile. If you are in Australia, you should contact SAGE-AU, which sponsors local groups there. Outside of Australia, things are less structured. This document tends to be most applicable to the United States, since that is where the authors have their experience, but the same basic procedures should hold in other countries. You will also need some space to meet in.