The legendary Neil Blevins has some great educational resources on his website (http://www.neilblevins.com/)I've learnt a lot from him and I really enjoyed his article on the use of color (A Study In Greens, Variety in Your Colors), which can be find here There is a maxscript called RandomMat that goes with the "Study in Greens" article on his site, here
He also has a whole host of Autodesk 3ds max techniques, scripts, tips and tutorials on his site. Many thanks to Mr Blevins for making them available for free :)