My daughter has a milk allergy as well. We have had APs for most of her life (she is three and our last visit was in February of this year).
As of February, there was no dairy-free ice cream at
Disneyland.
Ghiradelli does have sorbet, but they WILL NOT do an allergy order. Which means, they will not open a new container or use a clean scoop. We don't risk it.
Clarabelle's in DCA has a sorbet bar. They will do an allergy order and have someone (a chef? a lead? I'm not sure) make it in the back. They can dip it in dairy-free chocolate and add dairy-free sprinkles to it as well. It didn't stay on the stick (just keep it in the little wrapper and use a spoon), but it was very impressive and my girl was three shades of happy when she got it.
Dole Whip is dairy free. They only have the pineapple variety at Disneyland and it is safe for a dairy allergy. It DOES NOT contain casein.
There are some prepackaged items that are safe. I think I remember seeing repackaged Enjoy Life candy bars and some sandwich cookies at Pooh corner. I don't normally buy prepackaged items there, as it is much cheaper to just bring them in (and have real Oreos) on my own.
The popcorn is safe. The churros are not safe for us, but maybe that was just because of egg... The Mickey pretzels are safe, but are always on the hooks right next to ones with cheese, so we don't risk it.
The dairy-free pizza at Pizza Port is good. It only comes as the allergy pizza, on a gluten free crust and with Daiya cheese. The gluten free crust isn't bad, though.
I have heard that Haagan Daz (in DTD) will do an allergy order with sorbet, but we haven't tried it.
The french fries are generally safe. I haven't found chicken nuggets for my egg/milk/peanut allergic daughter yet.
This site has some allergy menus, just scroll down to find the Disneyland area:
http://www.glutenfreedairyfreewdw.com/menus/