This depends on so many factors. What are you planning to send? How large is it and what does it weigh? If it’s small and light, then it shouldn’t cost you much at all. However, enormous items will obviously set you back a lot more. Then it also depends on where you’re sending it from. If you’re in the USA, then it’ll cost a lot more than if you’re already in Australia or, better yet, Melbourne.
The best thing you can do is to type ‘courier Melbourne’ into Google. I can’t tell you how much you will need to spend on sending a package to Melbourne. Online, you’ll find price comparison tools and calculators to help you figure this out for yourself. In my experience, though, sending mail in Australia is quite affordable. You can find and compare courier quotes in Melbourne by following this link: https://fastcourier.com.au/same-day-delivery-courier-melbourne