Dan,
I am also doing an anglo concertina workshop at the National Folk Festival. I always try to get the anglo players together to share what they are learning, explore a tune, ornaments, stories, etc etc. I look forward to meeting you there.
I also help to run the NAriel Folk Festival each year and woudl be happy to help you make some contacts while you are here in Australia. Feel free to contact me. Cheers
Jamie Molloy