try going to
www.dirtcheapcameras.com (yes, they are australian)
from what i have seen though, canon powershot series cameras are very good for the price. Don't own one personally, but have seen some nice shots from them. umart.com.au also carries a few of the powershot series i think, maybe a little cheaper than dirtcheapcameras as well
as for accepting all cards, not many do that at all, and it is not necessary.