Have started to add a series of new procedural .blend files on my site for Blender 2.8.
Free to use, free to change, free to whatever you want and since it´s .Blend files and no images you can tweak the "#¤ out of it :).
NB! All files 100% Blender and 100% Procedural!
Welcome to my site; http://www.blenderinsight.com/material-for-blender-2-8x-cycles/