if you lazy to go check or wanna save a few bucks before going to the shop, then jack up your car, spin the front wheel and see if the tire moves up and down. if so, take out the wheel and change the position of which stud go in which hole, change the position of the lugnuts too.
might sound simple and strange, but sometime it fixed the problem -- temporarily. i fixed mine like that, but still, the problem is still there, just you didn't feel it. its still safer to go check allignment and balancing.