I think you can request a catalog. That's how my DGD picked out the doll she liked. You can also go to the AG site and "custom" make the doll choosing hair, eyes, etc.
As to getting a doll that looks like your DGD, that would probably be more in line with the Twin Doll. You send in a photo and they can match it very close. My nieces and grand niece have the Twin Doll and they very much favor them. The Twin Doll is a little more expensive.
My 5yo DGD got an AG doll for Christmas with a couple of outfits and I found some handmade clothes on one of the sites. HOWEVER, Analise (the doll) takes after Nana...stays in her jammies all day!! LOL My DGD says she needs lot of rest!!
My 8yo DGD got an AG doll for her birthday in December and by what they custom chose, the doll does look like her, even down to the cute little "bob" haircut.
I am entering into my "second childhood" playing with these dolls!