You need a letter from your therapist that you are affirmed female and Medicare, driving licence etc are just changed upon application. Birth certificate varies from state to state, but if married it is forced divorce. WeI have a bill before NSW, SA, Tasmania to have this thrown out. In NSW if you have problems Andrew Greenwhich will help you.
The driving licence, passport etc are enshrined in Federal Law, ATO need to give a new Tax File number. But again it is Fed Law. Many start with the legal name change then driving licence or passport as they are legal proof of gender identity. You can find all the documents by Googling them, if you have a problem I can guide you or the gender centre will help.