Imho if you're in australia you should just use the mobile option... it's just 5 bucks.
personally i've played over 2 years without buying any credits, but since i am currently studying in australia i tried it out once and thought "eh, what the heck, 5 bucks is like 1 meal". Should be quite simple if you have a mobile subscription.
Ah yea, then perhaps it would be hard... am from indonesia myself and most options were not available when i was there... i would tell you to make a paypal account, but even that was troublesome for me...
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