Have you heard of the on-line support group for Parents Of Food Allergic Kids?
www.kidswithfoodallergies.org
When my 6yo son was diagnosed with multiple food allergies (including dairy), I found this support group incredibly helpful. My son couldn't drink neocate (because of the corn if I remember right). But I remember many POFAK discussions about how badly neocate tastes (some breastfeeding mom's were actually drinking it themselves). There would be many experienced parents there that could give you advice and ideas for how to get her to drink it...
Have you tried one of the hydrolized dairy formulas? (If your doctor OKs it!) Our third child (18 mo) is also allergic to dairy, but can tolerate Carnation Good Start, which was recommended by our allergist. He was on Good Start for several months and did not react to dairy until we tried whole milk, yogurt, etc. So he is still on Good Start, even though he doesn't need to be on formula any more.
My understanding is that Allimentum and some of the other fully hydrolized formulas taste better than Neocate. (But they are still more expensive and taste worse than regular formula.) But, if the dairy allergy is severe (hives), I would hesitate to even try them. (Do talk to your allergist first too!)
-D.