Most Australian states have issued CD's and/or Microfiche with an index of Birth, Death & Marriage records, though some give more information than others. Also some of the CD's allow you to use an asterisk or a question mark to help you find the record you want. Birth records range from about 1905 to 1920 depending on which state you need, while some Marriage records go from 1937 up to 1949 and Death records can vary quite a lot with Victoria going up to 1985. Some states have extra years free on the Internet too.

Once you have found your Grandparents Marriage on a CD, your next step is to send for the Marriage Certificate which, hopefully, will give you the information you need to trace back another generation. Your Genealogical Society or Library can probably give you the address to contact to buy the certificate and probably the price, which varies from state to state.

This is enough information to help you get started, and I'm sure you'll get a real thrill when you end up finding out the names of your great-grandparents.!