I just found a great site. It’s from the association that many ped GIs register with (NaSPGHAN). It has lots of info about GERD and other GI conditions, but also has a doctor finder service. You type in your city in North America, and all the ped gi’s registered will come up. Unfortunately, you don’t know anything about them, and the contact info is not always there, but it’s good if you need to doctor shop.
Here’s the link: http://www.naspghan.org . Go down to for the public (if I remember correctly), then select doctor finder.