Is it legal to go to Australia as a tourist then convert your tourist visa into working visa?

It depends on what type of work visa you would like. The main options are: -Skilled migration visa: Lets you work and live in Australia permanently -Work and Holiday visa: If you have a degree and are from a list of designated countries you can work for up to 6 months at one particular ob and travel around. -Working Holiday Visa: Depending on your nationality (UK, USA, Ireland etc) you can work while traveling around. So depending on what visa you would like. The first option it would be best to apply in your own country as you have to show a low of documentation about your work and qualifications. If you want to do the 2 other options that you should apply from your home country.