I have recently discovered a website that is a must have for any developer who has struggled with picking the colors for their web site:

http://colorschemedesigner.com/

You get several choices to determine how to specify the colors. This option brings in a complimentary color in various shades along with the main color that you select on the color wheel.

You also have the option of specifying various adjustments to the schema. You can make it pastel, more contrast, less contrast, gray tones, etc. You can also view a preview page as a light page or a dark page to see how the colors might be applied.

Once you have everything the way you want it, you can switch over to the final tab and get the color list.

Now none of us have an excuse for questionable color combinations.