I suppose the Color Science forum would be the correct one to use - but no worries, this will do. 
I did a quick search in Wikipedia and found an article on NCS with some external links, including calculators and a viewer for NCS color:
http://www.i2studios.com/index.php?Page=http://www.i2studios.com/ncs/
This should at least allow you to convert to RGB values, and from there you can define what kind of RGB you’re using and convert to a certain flavor of CMYK using Photoshop or ColorPicker.