The really lazy way is to go to ebay and do a model of car+wheel search. They always list the bolt pattern. And actually there are not that many lug patterns most fall in the 4*100/4*114.3 or 5*100/5*114.3 Then you have your odd german car patterns for BMW, AUDI, MB. Trucks now all seem to have 6 bolt pattern. Keep in mind that the first# is the number of lugs and the second# is the space between the lugs from center to center. Someone correct if incorrect.