They are on Ebay and as Hank said, also Bunnings.

Seems a tad expensive at $2 a minute but OK if you don't have much work... http://www.bunnings.com.au/ross-mig-wel ... n_p6320518

A reg here... http://www.machineryhouse.com.au/O0171

More bottles... http://www.machineryhouse.com.au/Gas-Bottles

Although my MIG has a gas facility I have done all my welding gasless using flux cored wire and have had no significant problems. My new van chassis is being built out doors and therefore a breeze can blow away the Argon or CO2 protective gas.I therefore use a spray can of product with which you give a light spray onto the weld area and this helps reduce splatter and helps with a better weld. For gasless, remove the hooded shield from the torch head and most of all when gasless REVERSE THE POLARITY of torch and earth lead.

When buying a MIG look for a unit with plenty of adjustment to wire speed but especially to voltage settings to assist in a range of thicknesses. I think a dual purpose unit for gas and gas less operation will allow for any operation now or future.
there are lots of good tutorials via tube from which to choose.

Good health safe travel

George W.

Thanks again everyone for the info. I have now bought a MIG welder courtesy of Rory, and just need to get used to it.
Cheers.

I know it is too late re the purchase of mig welders however here are a few facts

Gassless is ok for small quick jobs however most gas welders can be used for both just by reversing the polarity of the leads in most cases
On the small welders most are only capable of 120 to 150 amps
Migs use less amps than a stick welder
Their main use is for light gauge materials where a stick welder would just burn holes in the job
They are also used as production welders

The smaller welders use mainly 0.9 mm wire max as most would have problems using 1.2 mm
So you only need to buy one size nozzles unless you use 0.6 wire

A couple of gas shields would be handy
You need anti spatter paste for the nozzle however you can use spray cooking oil as well

Liners are what the wire runs in
These are normally steel however these along with the mild steel wire go rusty and can cause feed problems
To use aluminum wire use as thick as the welder will feed and you must use a new steel liner but preferably a teflon liner

Disposable bottles for gas do not last long and are only good for small jobs
Rental bottles are expensive however last a long time

Argon is for alloy predominately or stainless
Argo shield is one of the selection for steel
Check with BOC for the correct gas for your job

Allan

Those disposable bottles can get expensive fast if you find yourself doing a lot of welding on a project, it's a real catch 22.

There are companies that will sell you a full size argon bottle and exchange it for another full one when it's empty, like is commonly done with BBQ gas bottles

This is one I've heard of, but I warn you that for whatever reason the company has decided it needs a photo of a girl in a bikini mig welding on their page. This made me smile but might upset some peoples sensibilities

http://www.speedgas.com.au/product/argon/

Sean