hey question where do I find evidence and a witness for the beauty and beast quest I've checked every where in the barons house and nothing
You can find evidence under one of the statues in the Baron's room. You need to do that at night when he sleeps. To make it stick you have to return to Baroness Xavier and update her on your find. After that blackmail the false Baroness with the found evidence so she will be an important witness later. After that return to Baroness Xavier and talk to her about the matter to start the end of the quest.