A lot of people have commented on how to fix the color (which I'm going to go back and read myself because I'm super interested in this). In terms of calibrating your contrast and gamma, however, this site has been IMMENSELY helpful for me:
http://www.lagom.nl/lcd-test/ Click the links at the top for specific tests. The most important ones are white saturation, black level and gamma calibration. I've been on monitors that look good, and then discovered my white balance is way off or the contrast is too high. Once you fix your color, you'll want to make sure your contrast/gamma is accurate, too.
Keep in mind, you're likely going to have to adjust your brightness and contrast through your video card. To do this, right-click on your desktop, and there should be a control panel for your video card (mine says "NVIDIA Control Panel" as an example). You may have to select "Use NVIDIA settings" in order to unfreeze the controls.