Beetlecat has a tutorial on coloring fur here:
http://beetlecat.livejournal.com/188117.htmlI painted the accents on my okami head with acrylic paint. It worked okay, but I probably wouldn't do it again. The fur was left crusty and impossible to comb in some areas, and blotchy and inconsistent in others. Since the accents were small, it wasn't as noticable as it would have been on a larger area.
I tried painting the accents on the body in the same fashion, but they looked so horrible, I gave up and hand sewed the proper color fur in place for the body accents.
I would suggest an airbrush or piecing together the pattern together with different pieces of colored fur before I would try painting.