I mostly pull colors from images, but http://www.colourlovers.com and http://www.wellstyled.com/tools/colorscheme2/index-en.html are sometimes helpful. FireBug is real helpful for experimentation.

The best advice I know regarding color schemes: spend time up front finding a good 6-8 colors to cover everything from backgrounds to link hovers, and then, stick with that scheme for your first iteration so that you don't get hung up on choosing colors all the time.