What type do you need/what camera do you have? You'll find them quite expensive here, especially the larger capacities. I believe Gecko Graphics and CSM2000 do have some, though I don't know which.

I've just brought in a few 2gb SD cards (Sandisk Ultra II) and I can let you have one of those for US$10. In cameras that take SD or MMC cards, which is the majority, only the newer ones that specify SDHC can take larger than 2gb. If you need CF I have a few old low capacity cards that you can have for free, just to make the camera function. If you have an Olympus that takes XD I think you'll be unlucky. In CSM2000 I've recently seen some Memory Sticks for Sony. Can't think of any other formats.