Unfortunately, with you being in Australia, I don't know what kind of access you are going to have to some of the internet direct builders out there.
From the pic that you posted though, you could shoot for companies like Axiom, Ascend, AV123, Aperion given the prices that I have seen, and still end up in the same ballpark w/ shipping and have a better quality speaker then Sony or Pioneer.
Audition the setups that you posted. Looks like a big box retailer. Hopefully they are setup to let you kick the tires.
Far as a $1000 5.1 setup, vs $2000 plus, you can do darn good for around $1000 US ($1200-$1300 aus?). Considering that you are looking at this for Home Theater, you do quality 2 way speakers for surround, MTM array center, and 10/12 sub.
What are the dimensions on your room?