What to do abut a hit and run accident?

You can go after the driver. You should speak with a personal injury attorney (even if you were not in fact injured, this is the sort of case, car accidents, they commonly handle and are proficient with). With the plate number, there's a good chance you and your attorney can track the perpetrator; if you can find him or her, you can sue for the damage to your car (e.g. cost to repair; or value of if it has been totaled, as you indicate) and other out of pocket costs (e.g. did you have to rent a car to drive?) or losses (have you missed any work days, and so lost wages?). The attorney can evaluate your case and the amount of losses and damages you've suffered in detail, and let you know how much you might recover, the odds or chance of recovering money, and also what it would cost to pursue the case; then you can make an informed decision as to whether to go ahead or not.