Agree with others about food and water and a litter tray (although if poss put litter tray as far away as possible from food). You could try putting some gentle constant music on so that the normal noises in the house dont freak her out too much. Save for changing her food, water and litter tray, let her come to you. Just go and sit in the room and speak softly (just read a book out loud if you like) and speak calmly. If she makes a move dont stop continue reading keeping your voice calm and soft and just let her do things at her pace. Make sure there is stuff in the room that will smell strongly of you such as a well worn cardy. If you can, isolate her in that room for now (or if you get the chance move her to another small room).
If she hasnt eaten for 24 hours, put some poached chicken, still in the broth down or some tuna in spring water.
Well done for adopting this little cat and also for adopting servitude. You'll be just fine.
This is Chapter 1 of the Cat Slave Training Manual. In Chapter 2 we discuss how kitty might get you to behave like this FOREVER!
She's scared beyond words bless her. She's had a horrid start in life and to her another change means another sort of danger for her.