We have used JCPenny's Portrait Studio for all of our pictures since my son was born. Both kid had pictures taken as newborns, 6 months, 12months, 18 months, and on birthdays from then on. I LOVE THEM! It could be our local studio, but I have hardly any complaints. Sometimes we get a photographer who tries to "pose" the little ones, and we all know that is really hard to keep a little one still for more than a few seconds. Offer to pose the child yourself (per their instructions) so they are ready to take the picture asap.
I think usually they have you scheduled for approximately 30 minutes, and we usually do two outfits. I really prefer the plain black or white backgrounds, but sometimes they have so other fun ones too. Also - ASK IF THEY HAVE ANY DISCOUNTS! It can get a little expensive sometimes if not. And I spend WAY too much money if I don't go in with a list of different size pictures I want. :)
Also, bring a toy or blanket your little girl really likes in case she gets bored or frustrated or tired.
HAVE FUN!