In a word...Yes(unless you're not bothered about saving your progress of course). I guess somewhere like ebay or just look around any highstreet shops such as GAME, Gamestation etc.
cheers tetlee, a bit confused bought a gamecube controller form HMV which on the frotn says for use with Wii, but physically i cannot connect it to the bottom of the wii mote, how do i connect it? they seem to be different shapes?
I'm sure you'll have discovered it by now but just incase, there's a second slightly smaller flap behind that one with the Gamecube memory card slots under it.