Are wheel lugs generally universal in size? Can I go to PepBoys to pick up the proper parts or will this require a dealership?

if your talking about ur bmw uh..
you dont have lug nuts

There are many differnt lug bolts out there. I'm sure that there are some at Pep Boys that will work, but the dealership prices on these items shouldn't be too much. The thread is M12 x 1.5 and its a conical seat bolt. These are crucial points, cuz if you get ball seat bolts like on Porsches, the bolt and wheel seat won't match up and you potentially could destroy your wheel (or car/self) if it breaks while driving. Wheel bolts at the dealer are a sure thing interms of length, seat and thread.

Check out Turner Motorsport for lug bolts. They have a bunch of OZ conical lug bolts for $1.25 each. http://www.turnermotorsport.com/html/detail.asp?PRODUCT_ID=4360