[quote name='iamthekiller']Can anybody chime in about the best way to avoid sales tax when purchasing games on PSN for a gameshare?[/QUOTE]
When setting up a dummy account for those people (assuming that's what you're doing) make sure that none of your addresses are in states that charge sales tax for online stuff.
Free DOUBLE tip: North Carolina, California, and Arizona do NOT charge tax, while New York and Texas do. I've also read that Utah and Massachusetts charge sales tax. There are obviously more that do/do not, but from browsing around a Google search, those states were ones explicitly stated (and well, NC is in there cause I live here)
I think (note: I, as in me, think, as in don't know for sure) it has something to do with Sony having a physical retail presence, much like Amazon has to charge sales tax in states where they have distribution centers (NY doesn't have one but still charges tax, though that's a whole loopy law about out-of-state sales)