ColorMine is an open-source library that is designed to make working with colors easy.
This project has been converted over to c#/.Net at http://github.com/thejoezack/colormine
This project has been converted over to Java at https://github.com/colormine/colormine
You can find more info, color converters, and delta-e calculators at http://colormine.org.
This version is very very incomplete.