I went in 2004 and just had a "paddock pass" as opposed to a grandstand ticket. We walked around the whole track during the preliminary races and the F1 race and ended up at the 2nd last corner for most of the race opposite one of the big screens.Melbourne is a good city for going out and it comes alive with the grand prix carnival. Lots of good restaurants and nightlife. You would want to get in soon to get any decent accomodation before it is booked out.
Try posting your question here http://forums.vwvortex.com/zeroforum?id=137 as there are quite a few people who post there who have been before and will provide tips on grandstands etc.
MK











