Nintendo has announced today that the NGC/GBA Link Cables are now for sale! The only problem is that you can only order them at Nintendo's Online Store and other online retailers.

Here's the full from the Nintendo newsletter quote:
" Using the cable, you can transfer data back and forth between the games. This is just one of many ways game developers are finding to take advantage of the Nintendo GameCube Game Boy Advance Cable, which is exclusively available at Nintendo's Online Store and other online retailers. To purchase a Nintendo GameCube Game Boy Advance Cable, click here."

I hope you guys got a credit card to order the cable ;)