A well-known designer trick I've used is to spend 20 minutes paging through a stock photo site (I like sxc.hu), find a picture you like with some good color contrasts, and pull it into an image editor to eyedrop colors out.

Kuler has tools that support this workflow too.

What I don't get is the "shopping for color schemes" workflow that sites like Kuler support by default. I have also never liked anything that came out of a "generate split complements" color wheel tool; the real aesthetics of things like triadic schemes depend too much on saturation/value, and not enough on hue.