Does "There are many sites on which you can find references or add-on tools for your rendering applications, popular sites include, Flickr.com and Deviantart.com. Both of these sites give artwork owners the opportunity to "market" their pieces under the rules of Creative Commons. (Please click here for more information on Creative Commons: http://creativecommons.org/about/licenses/" still apply if you didn't use any of the references provided by the site? Also what do you mean by add-on tools?