Gold Coast Stadium
Trains QR citytrains from Roma Street in Brisbane take just over an hour to reach Nerang Station, which is 1km from the ground. There is a free bus service connection for those that wish.
Buses Shuttle buses run from Pacific Fair in Broadbeach. The bus interchange is in the middle of a huge carpark which is free to park. Just park and ride the bus, all free with your matchday ticket.
Car Parking The short answer is ... there is none. There is a weird 2km exclusion zone around the ground which means no parking on the street whatsoever. There are carparks which Suns members pay for, but I'm led to believe there is no, or extremely limited, public car parking anywhere within reasonable distance. Public transport is the go. They are so anal about wanting you to leave the car out of the vicinity, you CANNOT be dropped off outside the ground or anywhere within about 250 metres AND it is policed!!!
Taxi Fares From the middle of Surfer's Paradise (Q1) to the ground took ~20 minutes, and cost $20 - $25. The taxi drop-off zone is on the opposite side of Nerang-Broadbeach Rd to the ground, and involves a walk of some 250 metres to the main gate.