Snow Suit is another product that's insulated and water-proof. Spendy.
If you are looking for something for some added warmth and you're that far south I'd look into Cabelas Dry-Plus or a Gander Tech-2-O suit. Both of these products come as insulated or un-insulated. I have the Tech from Gander and wear it all winter over some layered outer wear. The suit is un-insulated and it serves me well during our summer months as rain wear. I've never been wet in it and its a whole heck of a lot cheaper than any of the two cold weather suits.