I have since got in contact with Telstra and after talking on the phone with them for about a half an hour they will "check it out and see what they can do...". I don't know if this means anything at all, but at least they will check it out, I hope. If you are a Telstra Internet user and cannot access TweakTown, you can contact Telstra Internet Services on 131 282 anytime, which may just get them to take some action.

Update - Well it seems Telstra have fixed the problem. Lord Skippy let me know just recently that he can now access TweakTown, and he is a Telstra Internet customer. Good news, thanks go out to Telstra for fixing the problem.