DSE have Mac Book Air range on special don't blame me if you missed out. I saw it in stock for free delivery by the time I posted it.
Apple MacBook Air 13" 1.7GHz - 128GB $599.25 this one you have to try your luck (no delivery and most out of stock)
Apple MacBook Air 13" 1.7GHz - 256GB $749.25 delivered
And some more but I am not sure whether they are good price or not because I don't use Mac Book.
http://dicksmith.com.au/product/XA1002/apple-macbook-air-13-…
http://dicksmith.com.au/product/XA1003/apple-macbook-air-13-…
Not available anywhere in Melbourne for all three models:(