To find out who owns a car, typically the personal details of the registered owner are not publicly accessible due to privacy laws like GDPR. However, here are the common ways to find ownership information:

• Use car history or vehicle check services (such as CarVeto, FreeCarCheck) to get details about the vehicle's past owners, registration history, and other vehicle-related information. These services usually do not reveal the current owner's personal name and address but show the number of previous owners, ownership dates, and the region of registration.

• Apply to the vehicle registration authority (e.g., DVLA in the UK or DMV in the US) with a valid reason ("just cause" or "reasonable cause") to request the name and address of the current or previous owner. In the UK, this involves filling out a V888 form. Reasons accepted include legal issues like accident claims or vehicle theft. The authority may release details if the reason is justified.

• If you've been involved in an accident or need the owner for legal reasons, report the incident to the police or appropriate authority; they have the power to obtain owner information.

• Alternatively, if you have the Vehicle Identification Number (VIN), you can decode basic vehicle info and then contact the DMV or relevant authority with a valid reason to find the registered owner.

• Private investigators or legal representatives can be hired to locate the owner but this can be costly and subject to legal restrictions.

In summary, without legal cause, you cannot directly obtain a car owner's personal details online due to privacy restrictions, but vehicle history checks and official requests with valid reasons are the legal pathways to get ownership information.