Google wholesale butchers as that gives you a starting point.

Pakenham has an outlet which has good prices. Also keep an eye out for chicken breasts as they can be $6.99 or cheaper on sale. Next door goes to a wholesale place and says the prices are really good. They eat alot of red meat so for them it is cheaper. They also get them to cut up any large peices as there are only two of them

One thing I did was I sat down and thought about the cuts of meat I used. With a slow cooker you can buy the cheaper cuts.