Man I was just about to post a similar question. I know ifixit has them but I can get tri-wings cheaper and with free shipping on Prime (Amazon) and get it within 2 days. From researching people say the tri-wings for the nintendo products work (wii etc).
Only thing I'm wondering is nobody seems to know the size, this is what I've see listed for Macbook Pro tri-wing sizes
---> Y1, Y0, #0, #00, 3MM, 1/8... wtf, how can there not be just 1 size?
Thinking of this one:
http://www.amazon.com/TRIWINGS-TW10..._1?s=industrial&ie=UTF8&qid=1314920302&sr=1-1
As far as retail stores, you'll be SOL, some niche hardware stores carry them but only the bit's and not in the sizes needed for games consoles/computers. Don't even bother with lowes, home depot, or ace lol, they've never even heard of a tri-wing screw, even explaining to them what it looks like they'd say nobody makes a driver like that and I must be confused lol.... idiots