Andrew,
you can read the whole story here http://www.recreationalflying.com/forum/incidents-accidents/99036-ultralight-down-outback-nsw.html
I made the call on the area frequency and it was picked up by Melb Centre. Apparently, they cleared the frequency for me. Once I was down, they couldnt hear me and I was communicating with an RPT called Brindabella 399 who was transferring the info to both Melb and the CFI of Tooradin who was looking for me. There was about 5 aircraft that had left Tooradin to make the flight to Broken Hill and he wasnt far away.
Once he found us and assured Melb Centre we were OK, they cancelled the emergency.
I can still repeat the Mayday call word for word because I remember at the time hoping I wouldnt get into trouble for making it. Silly isnt it.
ATC was great and I cant believe how quickly and smoothly everything happened to find us and make sure we were OK.
Apparently my wife in Melb was informed that something had happened but that I was OK within half an hour of my Mayday Call
Boy did she yell at me when I got home
Cheers
Bryon