The way to get a freaked out cat to stop being freaked out at you is to ignore it. Tearing the house apart looking for it is one of the worst things you could do.

antongarou has the right idea about things. Wait it out. Leave treats in key spots around the house, e.g. on the cat tree.

It's a cat. He has his own opinions. If you were utterly terrified at a new surrounding, having arrived there in a cage, by means you do not understand, would you want the noisy giants chasing you around the place?

Wait. it. out.