You can find it http://www.radiantimaging.com/index.php?q=downloads/ColorCalculator" now. They changed their main webaddress.
http://www.radiantimaging.com/index.php?q=downloads/ColorCalculator
You will like this tool: http://www.radimg.com/dlcolorcalculator.htm
It's a free program and if I remember correctly allows you to load in your own spectrum (which I think you have, judging from your info) and do some color calculations on it.
Otherwise the abovementioned links, coupled with...