Vehicle Code Section 20002 makes it a misdemeanor to commit a hit-and-run:
The driver of any vehicle involved in an accident resulting only in damage to any property, including vehicles, shall immediately stop the vehicle at the nearest location that will not impede traffic or otherwise jeopardize the safety of other motorists.
Moving the vehicle in accordance with this subdivision does not affect the question of fault. The driver shall also immediately do either of the following:
(1) Locate and notify the owner or person in charge of that property of the name and address of the driver and owner of the vehicle involved and, upon locating the driver of any other vehicle involved or the owner or person in charge of any damaged property, upon being requested, present his or her driver’s license, and vehicle registration, to the other driver, property owner, or person in charge of that property. The information presented shall include the current residence address of the driver and of the registered owner. If the registered owner of an involved vehicle is present at the scene, he or she shall also, upon request, present his or her driver’s license information, if available, or other valid identification to the other involved parties.
(2) Leave in a conspicuous place on the vehicle or other property damaged a written notice giving the name and address of the driver and of the owner of the vehicle involved and a statement of the circumstances thereof and shall without unnecessary delay notify the police department of the city wherein the collision occurred or, if the collision occurred in unincorporated territory, the local headquarters of the Department of the California Highway Patrol.(b) Any person who parks a vehicle which, prior to the vehicle again being driven, becomes a runaway vehicle and is involved in an accident resulting in damage to any property, attended or unattended, shall comply with the requirements of this section relating to notification and reporting and shall, upon conviction thereof, be liable to the penalties of this section for failure to comply with the requirements.
Cal. Veh. Code § 20002.
While the person who committed the hit-and-run might not be found, in such cases, the prudent thing to do is to see whether you have an uninsured motorist policy (see Uninsured Motorist for more information).