Treaties are agreements entered into between States, either bilaterally or multilaterally. The Commonwealth, and not the States, is Australia’s international representative. It is within executive power to negotiate and execute such treaties but international treaties are not self-executing, requiring incorporation by legislation into domestic law (Encyclopaedic Australian Legal Dictionary).
Most treaties do not come into force when signed. They have a clause which specifies the requirements of the treaty entering into force. The clause may include a ratification date and a requirement that a certain number of parties have ratified before it can become law.
If you are searching for a multilateral treaty, a database such as the Flare Index to Treaties, which contains the most significant treaties from 1856 to the present, is a good place to start. This will help you identify the name of the treaty and provide a link to the text of the treaty. To find the current status information, you will then need to access the site where the material is lodged or deposited, such as the United Nations Treaty Collection.