I lived there for a couple of years... in the Patagonia where all the sick skiing is.  I lived in 2 ski towns.  Cerro Chapelco in San Martin de los Andes is ILL.  Also, cerro Catedral in Bariloche is super famous.  Cerro Castor in Ushuaia is pretty cool, i hear.  Last but not least, Las Lenas up north is the most famous ski area to north americans.  There are lots of other hills too, although they aren't as famous, but still have sick terrain. PM me if you want to know more about Argentina... I have lots to say
We gonna whack it til the wheels fall off.