Another Celiac family here, DH and DS1&2. If you haven't heard from special diets yet, you will soon, and I know they'll instruct you to do this, but be sure and return your dining reservations form with your reservation numbers. It's always a joy/relief to go up to the hostess and tell them our party is here, and have them say, "and 3 of your are dining gluten free today?"

Music to my ears!
Since it seems you're new to celiacs, {{{hugs}}} I've never been so overwhelmed than those first 3 months after DS1 was diagnosed. I totally feel your pain. It IS overwhelming, people in general have NO idea where gluten hides! The not knowing, and mixed-message information about ingredients like flavorings and colorings just makes you want to run screaming! There are a lot of great resources out there now, and the food (though pricey, so prepare your budget) is of SUCH better quality than it was 4 years ago! And it's only getting better. I recommend starting off at celiac dot com, they have a message board and some good basic info. You'll find tons of blogs and lots of information online... almost too much! So just take what you can absorb and don't put too much pressure on yourself. At first I carried a notebook so I could jot down what I learned was g/f and what was not, so I didn't have to rely on my memory.
It will get easier, I promise! And fortunately your Disney vacation will be a pleasure!!! I don't know if you're staying on property or not, but if you check out urbanspoon or otherwise google "gluten free Orlando" you'll find restaurants in the area you can visit, including Uno Chigaco Grill, Outback and PF Changs.
Also, I had a tough time finding info online for Ghirardelli at DownTown Disney, but at the restaurant they have an allergy binder at the register that is pretty detailed. We have been able to enjoy gluten free ice cream sundaes safely there, so don't be afraid to go in a check it out! (everything else is pretty easy to find online)
I have noticed lots of g/f folks here even though Im pretty new, so if you have other questions about celiac or g/f in general-not just Disney- I'm sure if you started a thread in the disABILITITIES Community forum you'd get lots of great info!
Best of luck, hope your girl is feeling better soon, and have a great trip!!!