Visit these sites for achieving good contrast:
Effective Color Contrast by Lighthouse International
http://www.lighthouse.org/color_contrast.htm
Colormatters
More color theory http://www.colormatters.com/colortheory.html
Color displays Graphics
http://www.webstyleguide.com/graphics/displays.html
"Browser-safe" colors Graphics
http://www.webstyleguide.com/graphics/safe.html
Screen Design Homepage Classes Homepage