Anyone know how/ where to make a cake like a little girls doll.  I am stumped 

If it's lying down, I would make the body and head of cake and arms/legs out of rkt (or fondant, if it's a small cake).  If it's sitting up, I would make the head out of rkt as well.

Depends on exactly what you're looking to do.  You could just stack some 6" cakes for the body, rkt head on top.  Add arms and legs.

Either way, you're gonna need to do some sculpting.