As a woman - I must say - all you have to do to get a restraining order is tell them he pulled your hair, hit you, etc. As long as you say it was done in the past, they won't go after him. But you will get your restraining order. If you have to have a mark on you and make a police report, do it.
The other option is a hitman, poison, or the like, but of course those are not REALLY options.
Also yes he is tresspassing on your property when he drives on your lawn. Call the police each time. Make tapes of your conversations (go to radio shack and tell them you need to tape your conversations, they will be happy to help or order parts).
Also, making a video tape of him trashing your lawn will do wonders. If the cops still do not want to give you a restraining order, take him to court with all the evidence.
L