Color Theory in Science and Art: Ostwald and the Bauhaus (Philip Ball and Mario Ruben).
Visual Perception and Aesthetics (Steven Ståhlberg).
Color Vision and Art (Webexhibits).
Color Printing in the Nineteenth Century.An Exhibition at the Hugh M. Morris Library University of Delaware Library, Newark, Delaware, August 27 - December 19, 1996.
Exploring the Color Image (Omens, W):
Online book on colour in photography, after Raplph Evans' Color as Seen and Photographed.
Color Wheel Pro - allows you to compare color schemes generated using the conventional artists colour wheel and the RGBCMY wheel. The colour schemes can be previewed as web pages, packaging or logos.
http://www.color-wheel-pro.com/index.html (free trial)
Color Harmony Chooser. (gives the two other triad colours on a 12-colour wheel)
Palette Master (Nebulus designs).
(There are many more of these devices available both online and for download, but most use only the naive RYB colour wheel, and so are essentially useless.
http://www.genopal.com/pic2color (get colour scheme from a photo)
http://genopal.com/pcmac/demo (generate by setting proximity to starting colour.
Color Symbolism Chart by Culture (Jennifer Kyrnin)
Color Communication & Symbolism.
Paintmaking.com (Tony Johansen): Large site on pigments and their history.
Handprint guide to watercolor pigments (Bruce MacEvoy)
The Color of Art: Pigments (David Myers)
Artists' Palettes and Colour Mixing (ColorAcademy)
Pigments Through the Ages (Webexhibits).
Burnet, John. Practical Hints on Colour in Painting.
Parkhurst, Daniel Burleigh. The Painter in Oil.
The first ten years of Photoshop (Jeff Schewe)