I know of many people in Adelaide who keeps crocs. they are relitivley cheap too, around $450 for a 30cm freshie. I wouldnt mind one, but we use our pool too much
I visited Darwin's Crocodylus Park in 2007, and I believe that they have about 8,000 crocs there. There is enough scaly guys to send all over Australia, but I'm not sure people realize how large some of them grow up to be. Even the freshies can attain a decent length and unless folks have swimming pools the crocs would certainly outgrow a bathtub!
i beleive you have to have a pond or have somone to take on the croc when it gets to a size, i am not granted for Crocodiles so am unsure of the requirements, i will make some enquiries when i am back in SA.