I know your pain, I also live in Perth and i get about 300-500 ping on *anything* i try and play online, be it DOD, ESF, Battlefield. You name it. Very annoying, sometimes i can find one or two servers that i get a ping of about 200 on, once i even found 100 but its rare and they never stay around long.
If you find anything i'd love to hear about them also