Camping with easy access to Sydney city centre?

Hi,

Can you help me with the following questions?

My friend and i would like to camp close to 'easy' public transport
into Sydney city centre... can you recommend a good campsite? (perhaps
there is a good camp site close to a train station??)

Also, we will be driving down from Brisbane... any suggestions on what
is worth looking out along the way? What would be the best route for
enjoyment?

Thanks a bunch,
Jay