Attached Link: http://www.templetons.com/brad/copymyths.html

It doesn't matter if you intend to charge for your item or not... using something and REDISTRIBUTING without permission is a violation of the original creator's copyright. Money or intention makes no difference. Some artists don't mind or even encourage the modification and reuse of such things as textures... and they have explicitly said so. But, unless you have it in writing, don't just assume that it is ok. Carolly