Check out http://www.gamblincolors.com/newsletters/getting-the-white-right.html
I love anything related to art and got this new newsletter site the other day from Gamblin Artists Colors. Granted it is a bit technical and lengthy, but we all owe it to ourselves to learn as much as we can about our process and tools. I read the newsletter in small increments to avoid information overload. It is very informative. A few days back I reviewed the new Fastmatte oil colors from Gamblin, did not give them my seal of approval at that time, but now after reading more on the subject, I am going to try the colors again. They are well suited to someone who paints with deadlines looming over them.