I would use a cheater bar, but I let my friend borrow it to work on
his '73 chevy pickup. :/  Looks like I'll be driving over to his place
later if I still can't get the bolt/stud's free.

For the lug nuts themselves, I usually wire wheel them clean, dump
them in degreaser for an hour or so , and then liberally apply
anti-seize. :D

sudhir