Lady Musgrave or Lady Elliot Island would be my pick if you're on a budget and you don't mind roughing it a little. There's not really much shore diving worth doing in QLD. The water close to shore is quite turbid and muddy (also may contain sharks, stingers, and crocs
If you can get off shore you will have a much better time.
Where are you planning on going in North QLD?
James
