Dude, they don't card you for lighters..at least not in the U.S...run down to 7-11 and buy a 4-pack of BICs. Or whatever the equivalent is in Australia. I'd be surprised if there was an age limit for purchasing lighters there.

Seriously, I'm pretty sure anyone can buy a lighter, anywhere, for any reason..

And if you really can't get out of the house to buy one (i've been there), matches do the job. Even a candle, though the dripping wax pisses me off.