Hi Sheryl,
Welcome back to good old Canberra.
There are plenty of Playgroups around Canberra. My advice is to call this number on Monday: 6207 9977.
Its the number for the ACT Child, Youth and Women's Health Program - they are a wealth of information, they have nurses just a phonecall away, provide you with info about drop in clinics (around your side of town) to weigh bub or ask questions, you can see a physio, speech therapist and its all FREE!!!!
It also includes a list of playgroups. The ladies will recommend the closest playgroup to you, some are conducted by ACT Playgroups Association (they have a website also), others are mother's groups who meet from house to house or one location to another.
Also, I recommend getting the dates for paint and play (its yet another free event) at a park where the kids run riot, make lots of mess and you don't have to clean up. Its guaranteed to put your little darlings to sleep on the way home...lol
Hope you can find a playgroup and if you can't let me know you can join ours.
Hope this has provided you with food for thought!!!