What site(s) do you recommend for looking at complimentary colors for site design? It would also be beneficial to enter a hex or RGB value and have the color wheel spit back complimentary colors.
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Adobe's Kuler - http://kuler.adobe.com/
is widely considered to be the best color palette selector out there, as it also lets you share color palettes other users have created. Sign in, click create, and you'll have options including "complementary" that give you a good starting point if you have one color in mind.