TheHut.com online store has a great End of Summer Sale going on right now with some exemplary deals on console games.
Some examples (prices have the £2.35 postage cost added already):
Mirror's Edge (360) £10.08: http://www.thehut.com/hut/9992056.product
Naruto Rise of a Ninja (360) £12.28: http://www.thehut.com/hut/10050915.product
Dead Space (360) £13.28: http://www.thehut.com/hut/9979075.product
F.E.A.R 2: Project Origin (360) £16.28: http://www.thehut.com/hut/10026527.product
Bioshock (360, Steelbook) £16.28: http://www.thehut.com/hut/8599640.product
House of the Dead Overkill (Wii) £12.28: http://www.thehut.com/hut/10021338.product
Little King's Story (Wii) £17.28: http://www.thehut.com/hut/10026533.product
Bioshock/Oblivion Double Pack (PC) £14.78: http://www.thehut.com/hut/10048027.product
Half-Life 2 Orange Box (PC) £14.28: http://www.thehut.com/hut/8631188.product
There are heaps more gaming bargains on their site so if you find any outstanding ones, please point them out in the comments.
By the time you convert to AUD and then add on postage i don't think you are going to save much money.