Your ISP probably has a good route to the US west coast.
Correct! Australian ISPs are either routed through South East Asia or NA!
The best way would be to use a VPN or as Maia said the AOL cheat (Log into AOL, create account and log in to the game then close down AOL) - This does hide/change your IP since many IP banned people use it, but for cross continental I'm unsure.
I don't know any American VPNS but they are the ones you want @Kaeporo playing from a different country won't be ideal but you must do one or the other. They're only $30 odd a month.