When taking sculpey commissions, kodama are available as commissioned pieces. They're each $20.
To the best of my knowledge, kodama (or at least this incarnation of them) are property to Miyazaki and Studio Ghibli. They appeared in the film Mononoke-Hime as cutesy little tree spirits that help Prince Ashitaka find the lake at the heart of the forest. They resemble wind-up bobble-heads and the only other input I can think of is that they are insanely adorable.
Oh wow *checks wallet and sighs* wish I had some money they are adorable >.< as soon as I get my next paycheck I am going to try and make a bobble head of a Kodama and try to make it's head rattle XD if I do I'll be sure it up on here, maybe if I'm successful I'll sell some ^^ So cute you are very talented how did you make them?