Well, I'm no genius. Anyway, I made a Toad sprite and I decided to move it up the ladder as far as spriters go. First I come here, and if it's good enough for here, I move up.
Good, but I'd advise you to make the shading a bit more...extensive? More contrast. And don't forget to shade the line. It is a clean job however, and I noticed a good amount of detail and several parts.