While I haven't really been in the market for this kind of stuff in years, I'm pretty sure that I'm not grossly lying to you.
You can find it at Radio Shack or any similar store. If there's a local bulk electronics supply warehouse, you might be able to get a cheaper deal per foot, but I wouldn't expect the unit price to be cheaper than at Radio Shack. Same deal goes for online.
Are you planning on doing some mass wiring, or giving the leftovers to someone who does? If so, then looking online isn't a bad idea. If not, you'll save a lot of headache by just buying locally.
You should also consider asking around if people have extras, since there's no way you're using that much wire for a single stick.