It's relatively easy to perform dollar cost averaging in Australia. You'll just need an account with a trading platform or broker that offers access to the stocks you want to invest in. It's worth finding a broker that offers a low, percentage trading fee (or no trading fee at all) when using dollar cost averaging.
Once you've created your account, you then just need to may regular fixed investments over time. Many platforms also offer an auto-investing feature which you can use to set up automatic dollar cost averaging investments.