Well, I don't know of any specifically for ponytails. However, if you or someone you know has a ponytail, you can look at her (or his :P like my RP char, lol) hair to see how it works. Basically it depends on whether it's up "high" or "low." Have the strands of hair basically heading towards the center of your ponytail, and if you have a part (if it's a low ponytail, usually), then make sure you include that as well. Once that's done, add the ponytail. Use slightly brighter shading if it's set against the hair, to distinguish it, but if it's just off to the side or away from the hair, then just keep the same shading. The hair should "pinch" at the hairband and spread out a bit or a lot, depending on the length of the hair. If it's pretty short, make it spread out and spiky. If long, spread it out slightly, but keep the hairs relatively close together. Taper the end a bit, and then you have a lovely ponytail!
Lovely doll so far! Hopefully this will help you.
