An acquaintance of my elderly father (waitress where he eats)has convinced him to sign everything over to her and to give her full power of attorney. Do I have anyway recourse?
You should contact an estate attorney immediately. Typically when a person that has living family members creates a testamentary instrument gifiting their belongings to someone that is not related there is some form of duress. If this can be shown, i.e. she has been telling your father that his family is taking advantage of him and only wants him for his money, then the instrument can be voided.