Um, I'm in Australia, but i got it at a shop Called 'Off Ya Tree'. They've got HEAPS of stuff for every rock/punk/metal band that's widely known. I wanted an AC/DC hoodie, but I'm kinda broke, and it's gunna be summer soon, so there's really no point. I'll get it next year...
I also have an old AC/DC badge that someone made for me. If you can get your hands on a badge maker, they're brilliant. Try at your local school, my friend borrowed her badge maker from there.