Yeah Ducky, I think you'll find the only shop in Adelaide is Sports Card World (for packs/singles). If you're in the suburbs, maybe try a newsgaent, as they may have single packs (but these are generally retail packs, not hobby, and usually Upper Deck).
There are probably a few other places that stock collectibles (like posters, big ticket items etc) at places like Kollectable Kaos.
How long you in Adelaide for, when are you here, and where you staying, if you don't mind me asking.