The Bowhunting Fourm is a catch-all for archery.
The topic of a kid's bow has been discussed on there several times, I've got a 9 year old shooting a vertical bow and x-bow - she's having fun.
I went with Mission bow (Craze) that will adjust from 10 pounds at 17 inch draw to 50-60 at 28-30 inches - she can, and has grown with it over the last three years.
I'd suggest the Archery Pro Shop - most will let you try out a demo to see what she likes.
