there's lots of places.. but i just got a sweet deal off
www.buy.com for the dane-elec 2GB microSD card.. it was $10 with free shipping yesterday (special deal). ALSO, if you are new to google checkout you get $10 off (so I got my card for free!!!) I've been looking for deals and decided to go ahead after GPS as well.. 2GB is plenty for me, plus 4GB is a huge jump in price.. The nice thing about buy.com is the sweet google checkout deal- but don't be afraid to look around.