carry around with you some marble sized stones i.e. gravel.
as they get close just throw ane out your window - let him see it if possible
every so often throw another and he will soon get the message - this works a treat.
make sure you report him to the coppers as well.
generally i have found that whilst there are cowbotys all over, the drivers with the dogs in qld are the worst. the way they drive its little wonder that there are rollovers all the time on the freeways there.
