Your best bet is online (if you want to save money on it)..even though I'd be a little weary
I ordered the black GC mem card from amazon.com and received a 3rd party version that looks so awkward...but im not one to complain for $10
Also, I don't think there is a need for you to get the white memory card...unless your big on gc games, there is no way you'll have that full (just helpin a bro out)