Well, again the body is a simple ball, as are the round things on it's head. The limbs are just small ovals. The features and drool could be painted or stitched/glued on. And the leaves are just pointed ovals, though I don't know what kind of material to use.
As for stuffing, I'm pretty sure that you can get commercial "art fluff" at craft stores. XD There, advice from somebody who's never made a doll. What am I doing?