i dont think u can find the owner, wthout the help of traffic police.
Traffic dept has got the database, if they input the vehicle number, they get the whole info of the owner
once we could not remove our car from the garage , bcasue someone parked car in the street but infront of the garage. we waited for sometime atlast my husband informed police. the plice took the vehicile number and after 5 minutes they called backe and told us that they have instructed the owner to take the car. Also police gave the number , to call him again,in case he doesnot turn up within 10 mnutes.... so pls go to police