If you have assets , like a house , then they can get a charging order and an order for sale to get their debt back.
I know this because I kicked out some guy from a flat I owned because he was using it to distribute porn DVD's.
He sued me for about 2.5K and my solicitor told me that if I didnt pay then he could get a charging order and an order for sale , I paid him off and then wrote a letter to the local papers , who wrote a big spread on it.
There are some creditors you have got to pay like Council Tax and any fines you have from a court for things like parking or driving offences otherwise you can be put in prison for non payment.
Everyone else including Income tax you can either make an offer or use an IVA before they try and make you bankrupt , which is the only way they can then get your assets.
If you go to court and make an offer of payment and the courts accept that then providing you keep the payments up its end of story.
If you have no assets then you will find that most creditors wont bother , there is no point in spending more money to get nothing back, and making you bankrupt will cost them 2-3K at least. You will just end up with a lot of CCJ's and no line of credit for 6 years.
Also the courts have to be certain that you have been served any papers , the creditors have to prove that you personally received the court papers before they can go much further , so if you scarper then no court action in theory could be taken against you although I wouldnt trust judges to abide by this courts are nothing but a lottery , do not expect them to uphold the law , you will be lucky to find a judge who knows the law.
I would advise you to write to your creditors and tell them about your situation and offer something , even if its only 5%. Write out a budget that you can stick to. Most creditors know that taking you to court will only result in the same thing at court so might save themselves time and money and accept your offer.
I would advise against just taking off , back in 1980 I lived in Aus for over 4 years (Not because of any financial problems) and found that although its a great place you will find it to be quite isolated , my wife also found that making friends there was quite hard so you might find yourself wanting to go back , you will also find Sydney expensive.