When you start diving, like most you will probably end up renting your scuba equipment from your local dive shop (LDS), if you get bitten by the bug you will soon be considering buying your own gear. If you cant invest in a full set start with the things that are most important and then build you kit over time.
The first piece of gear that you will most probably purchase is your mask and snorkel and it probably wont be your only set, personally I think I have six or seven. After this you will want a good set of open heal fins along with boots. Next an exposure suit and depending on where you do most of your diving will either be a wetsuit, dry-suit or both.
Depending on what gear you select you will probably end up spending around au$3000. On the following pages I will share some links on where I have found some decent prices. There are a myriad of places where you can purchase your gear.
The best place to start is your local dive shop as they will also provide advice on the correct configuration for your needs. There are also thousands of online options, here are a few that I have regularly purchased from: