There's this company called Wheels For Fun. www.wheelsforfun.com.sg
They do have some packages - including 1 day trip.
From what i heard (i could be wrong), they pack you off in a bus at 3/4 am on raceday, drop you at the circuit (the ticket is a hillstand) and drive you back to singapore after the race. no hotel accomodation required. this is the cheapest option, i guess.
Yay thanks. I actually found them while trying to search for package tour. I've called them and they've email me. 2D1N for $506 with or without GST? and inclusive of RM150 2x C2 Hillstand w/ Cover stand.