For Los Angeles Used Cars, Ad listings for the following major makes of cars which may be by private owners and car dealers (note: if you are looking for Los Angeles Car Dealers specifically)

Acura / Honda
Audi
BMW
Cadillac
Chevrolet
Dodge
Ford
GMC also Cadillac, Chevrolet
Honda
Infiniti
Jeep
Lexus
Mazda
Mercedes
Mitsubishi
Nissan
Porsche
Toyota
VW / Volkswagen