I just don't think springs are his issue, I think it's the shocks all the way, I'd fix those and worry about the springs later, unless he has a few hundred he can spare to blow on springs too. Lowering the car leads down a sticky path of camber and all that crap.

I'd spend say $100-200 and replace the shocks with some brand new OE spec equivilents from Autozone or something before I did anything.

Or just go to www.Shox.com or www.Tirerack.com get some good cheap sport shocks and call it a day. Springs I'd do used, but shocks would have to be new all the way.