Summarize:

Most vehicles have the VIN etched or in the form of a sticker on at least two parts of the car. Look for the VIN on: The driver's side in the door jamb The driver's side dash board Metal within the engine compartment Parts of car that can't be removed While you should be able to find the VIN on the actual car, it might be easier to find it on the car's paperwork. This will come in handy if you don't physically have the car, but have some paperwork associated with it. Look on the: Title Registration Repair records If you don't own the car yet and can't access it, you can ask the seller of the car for the VIN. The seller will be able to find the VIN just like you could through paperwork or by looking on the body of the car. Make sure the seller provides you with the entire 17-digit VIN number before you commit to buying the vehicle. The seller should happily give you the number so that you can do an independent vehicle history search. If they don't, they may be hiding something.
Find the VIN on the car, if you have access to it. Look for the VIN on paperwork associated with the car. Ask the seller for the VIN.