I'm glad you're liking Safebooru! There's lots of fanart here of your favorite anime. If we don't have the fanart, let us know what we are missing out on and we'll have it asap, if we can. Safebooru is a good, strictly safe image gallery site.
Not only is there fanart, but some really cool original art too! The site hosts pretty much anything drawn in anime style, so you'll definitely find stuff you like!