As crazynites said try ebay. You can get 2nd hand PS3's (40gig) for a pretty good price.
Also, Big W had PS3's for $600 back in December. They may repeat that deal within the next couple of months.
I won't buy a ps3 until MGS4, so I'm either waiting for a good deal from kmart/target/big w, etc. or I'll pick one up on ebay if I see a good (& legitmate) deal.