The cheapest prices I found for the Apple iPad (in Australia).
16GB Wifi $529 (SOLD OUT)
16GB 3G $719
32 GB Wifi $659
32GB 3G $799
64GB Wifi $779
64GB 3G $899
Delivery $9.95
Please be aware that there will be soon a new version of the iPad … so discounting will be very common for the "old" version.
I also would not suggest the 3G Version if you have an iPhone … the next software update (4.3) should introduce a Local WIFI Hotspot. So you just need your iPhone to connect to the net.
EDIT: The WIFI Version does have no GPS … so when you need GPS you need to buy the 3G Version … thanks iampivot, tethering might be prohibited on your mobile network … so check your contract, Android phones have that functionality already and will work as a WIFI Hotspot, some people still prefer 3G build in … :-)
EDIT: The 16GB Version sold out … other versions still available.
+1 for good contextual information. Thanks OP!