New Horizon Business Services Inc.

Can you file for bankruptcy in a country such as Australia when you no longer reside there? I moved to the US 4 years ago, and have not been back since. I have just recently (this week) been contacted by a debt collection agency demanding full payment in 30 days on a debt from 2004 for which would be impossible to pay. The debt in question was a $25,000 credit card bill that has accrued interest to an outstanding amount of $50,752. I would struggle to pay $50 a week let alone the $50,000 in question. I do own a small town home that has no equity here in the United States. My family lives on my single income to support my wife and children. I could not afford for them to have the debt transferred to the USA and have my wages garnished or have my property have a lien placed on it. What are my options for filing bankruptcy? Can I do this from the US; can I retain my home here for my family if I do so? Any help would be better than making more bad decisions. Thank you B