Other than the iPhone 4, are there any Microsim phones on the market?

I just got an iPhone 4 contract though 3 Australia, but the iPhone wasn’t working right when I received it. I’ve sent it back for repairs, but until I get it back, I have no phone because it uses a microsim.

So my main question is: Are there any cheap microsim phones I can buy to use in the mean time?

Or is there a cheap way to make my old iPhone 3G take the microsim?

Also: Does anyone know how long it takes Apple Australia to fix iPhones?