To find the ghost, wait until Monday Nights after all stores have closed and before 4:00 am, go to the south-east corner of your town and you will hear a voice. Follow the voice and wisp will ask you to find his lamp for him. Go to the attic of your house and there it will be. If you do so, he will either give you a randomized gift, clear all your weeds, repaint your house, or clear your house of cockroaches.