Fr. Robert Spitzer explains how to recognize evil forces in our lives and overcome them. Through Jesus Christ we can be transformed and fight evil instead of being controlled by it. In the battle of Jesus vs Satan, Jesus will always win if we just let him.
Another good resource for the fight against evil are the saints and angels. In times of particular temptation, ask for the intercession of St. Michael the Archangel, your guardian angel, and St. George.