I bought a new Cube from eBay the other week and it arrived today from America. I knew that it would have an American plug (I'm in Australia) but the website says it has multiple power supplies.

Is there some way to switch it to a different power supply internally? Is it better off just buying a step down transformer to avoid hassle? Any circuit diagrams or anything would be helpful too, I couldn't find any on the internet for the life of me.

Any help is appreciated.
It's actually a power soak. Bumps the watts down to 5. So you'll need a stop down transformer.
Are you referring to the power squeezer? because thats not what I'm talking about. On the stats table of the Cube it says this:

Power Supply AC 117 V, AC 230 V, AC 240 V (50/60 Hz)

Which means, I think, that it can run on these power outputs. 117 V being American and 240 V being Australian.

I'll probably end up getting a transformer at risk of damaging it but I'd still like to know if anyone can tell me.
I was thinking earlier, would it be worth taking to the local music store? or would it be better taking it to an electrician?

I need help because I want to play it already!
All you need is a Euro able cord. It just has to match the three prong input that the amp has and the output section of the amplifier will take care of the rest.
So you're saying that if I get an adaptor that doesn't have a transformer in it the amp will just switch accordingly? How sure are you about this? Considering I don't want to blow it up if it doesn't work.
God damn Roland! I just called the support line and apparently they do not supply support for items that were bought over eBay because they "do not actively encourage the selling of items over eBay". **** them! The bloke refused to tell me if it would work or not on Australian power.

So I still need a little more reassurance on what to do. so as usual any more help would be appreciated. This was more a vent of my anger than anything else (but also a subtle bump).