The first exchange I used was Mt. Gox but I lost interest in Bitcoin shortly after making my account there. Over the past year, I made a few small purchases off LocalBitcoins which I've been quite happy with.

I'm not a trader and my experience so far has been that while the prices are a little bit higher there versus other exchanges, the volatility of Bitcoin makes this pretty much irrelevant especially for smaller-sized purchases.


Oddly enough, there aren't that many exchanges in Australia at the moment so your choices are pretty small. You could try this one:

http://www.independentreserve.com/

I think they're currently the biggest one there.