I've tried to find out what the laws really are several times, and each time I've given up without knowing the full picture.
If you want to sell meat, you need to have the animal killed at a licensed abattoir, transported via approved refrigerated transport to a licensed butcher, and cut and prepared there. You can then sell it. Butchers don't slaughter here in Oz (there may be exceptions, but they'd be very rare). There doesn't appear to be any way to kill on-farm for sale, unless you have an inspected abattoir and butchering facilities on-site. I've never heard of anyone who does that.
I've bought beef this way - I paid for the cow, the farmer had it transported to the abattoir, the abattoir organised transport to the butcher, the butcher cut and bagged it to my instructions, and I picked it up from him. Of course everyone takes their cut along the way. I don't like the disconnection, though - I was supposed to get the offal from two cows that were sent up that day, but I only got one liver, three cheeks, two hearts, two tongues, no kidneys, and no explanation of the missing bits. You're never quite 100% sure whether you got everything from your animal, or indeed whether you got your actual animal back - I've heard horror stories, but I think the people I dealt with were fine.
When I raised some pigs, I tried to find a mobile butcher who could do everything on my property (the meat wasn't for sale). The one guy I found said he no longer did it because the regulations were too hard to comply with. I've heard that there are mobile butchers in other regions, though. In the end I had to go the abattoir/butcher route.
I have heard that meat you raise and slaughter yourself can't leave your property, but then what happens for farmers who don't live on the land they slaughtered on? The rules must be a little flexible there. I've also heard that you can't serve the meat to people who don't live on your property, but I was told by one of the government departments that that's not true - dining guests are fine. You can't serve it to commercial guests, though - e.g. people paying for farm-stays or paying you for a meal.
In the end, I stopped researching because it was too difficult. I don't want to go full commercial, I just want to be able to sell a few rabbits, ducks and chickens to friends and family. Turns out it's more hassle than it's worth, so they only get to eat my critters when they visit me

.