Apologies for the delay in replying guys.
For those staying overnight, I've found the following accommodation on Wotif:
Chifley Eastern Creek
The Chifley is literally 100 metres from the front gate of Eastern Creek Raceway, its modern and clean and a delux room is only $104. Obviously I'm not sure how many rooms they have so you might want to jump on and book a room as quickly as possible.
Cheers,
Richard