I dropped one while soldering and I can't find it anywhere. I'd rather not pay for 100 of them and wait till it arrives from China. Does anyone have 1 they could sell me? I'm fairly sure it's these.
I'm near Charlotte NC IF that matters.
Radio Shack?
Take your wallet. One from RS is close to 100 from China.
Radioshack doesn't have SMD's, or they didn't last I checked :-/
Why not buy from digikey? You'd have it in 2-3 days (at about the same price total as from china - and you could get some other common cheap passives while you're at it)
104 = 0.1uf (the most commonly used value of cap).
Make sure you get the correct size - the one you linked is 0805, but they come in other sizes. You can check the sizes against this chart or the size heading in the digikey catalog.
DrAzzy:
Radioshack doesn't have SMD's, or they didn't last I checked
Well, I wouldn't know to be honest - they died a prolonged death in Australia.
We have Jaycar. But checking their cattledog shows they don't have SMD either. 
DIPmicro
http://www.dipmicro.com/store/C5J10-0805
http://www.dipmicro.com/store/C5J10-0603
What size?