Best entry level camera (and most likely the cheapest) at the moment is without a doubt the Pentax K-x which can be had for around the $699 Aus dollar mark. Only reason i'm chiming in now is because i've only just been doing some reading on it and it's low light performance is quite amazing for this price range, being compared to the most expensive APS-C format cameras. Plus I think it's the only entry cam with shake reduction tech, can be used with any pentax lens ever made (unlike Nikon entry level cams which are crippled. Their mid to high end is great though) and one of the only with HD video? correct me if i'm wrong.
Buying Pentax gear is no issue here, all the major stores like JBHifi, Teds, Officeworks, Digital Camera Warehouse, DickSmith, etc etc will stock it not to mention the many privately owned camera specialists who can probably get you a better deal than the larger chains.
Only real consideration is if you want to buy into the Pentax lens system.
DPReview
"no doubt one of the currently best performing APS-C cameras in low light."
"Pentax has managed to squeeze what is, for this class of camera, an impressive feature set into the camera's minuscule, rather inconspicuous, body and the image quality, especially in low light, is the best we have seen so far in the entry-level bracket of the DSLR market. To put some icing on the cake, all of this comes at a currently, compared to the closest rivals, very attractive price point. To us the lack of visible AF points is the camera's only real drawback but if you can live with this omission you can't go wrong with the Pentax K-x."