In reply to Adam_Turner:
Adam,
You don't make it clear from your post whether you want to climb the Polish Glacier route or the Polish Glacier Direct route. You might find some companies guiding the regular Polish Glacier route. However the PG Direct route is steeper and more serious, I'd be surprised if anyone is offering to guide it as an open expedition, you'd probably need to find a private guide for that one.
I have been on the Polish Glacier route twice with a reputable expedition company (as the guide!!). It's a nice way to the summit if the conditions are good, but the conditions can be pretty variable, and this winter has been a dry one in the Andes so we may end up with icy condition this coming Austral summer.
At it's easiest the Polish lacier is just an alpine PD, a couple of short sections of snow to about 40ยบ and a couple of narrow exposed sections of ridge. It would not be a good route to do in windy conditions (frequent on Aconcagua). Worth also saying that the biggest avalanche I have ever seen swept down the whole glacier one year, so don't go after recent snowfall.
John