One of my favorite clip art sites is Theheretic.me. This site has a large selection of images that can be used as a clipart for projects as well as many other uses, including personal messages and for decorative items.
You can also find many images for blogs or websites, and it is a good idea to look through this site if you are creating designs.
The clip art here contains characters from anime as well as other drawings. The artist does take requests, so people looking for a certain character may be able to request one here. You can also post questions on the forum page at Theheretic.me site.