http://hydra.cs.utwente.nl/~andernac/icons/othericons.html
This Web site has a large collection of bitmapped icons for all types of uses. Some are black and white, some are multicolor. If you just have to have a Bart Simpson icon, you can find it here. There are various sizes, and subjects, and all have been collected into compressed files making it relatively painless to download the whole collection.