They're usually sold thru auto parts stores but I'm sure they're online as well. I had one for a Buick SW I owned which had such a shiny dash it reflected in the windshield and interferred with the view of the road.

They come in many colors and a few fabric surfaces but not likely to match your interior exactly -- just close. They are usually attached with velcro so you'll have to stick a few pieces of velcro to your dash. This is necessary since they slide so easily and you want to keep them from blocking things like defrost vents. Overall I was satisfied with how well it worked.