Nov. 20/24-The crew of C-FAAF (a Transwest Air Piper PA31-350 Chieftan) was planning a flight from Stony Rapids, Saskatchewan to Fond Du Lac. They noted 3 pilot reports that indicated no icing below 4000 ft ASL along their intended route. After departure, while climbing through 2500 ASL the crew observed ice accumulation, and chose to descend to 2000 feet and continue VFR to destination. While enroute the crew noted that the windshield had iced over, and visibility could not be maintained. They elected to return to Stony Rapids, however upon arrival they still could not see out the window. They declared an emergency, and circled in an area clear of icing until the windshield de-ice was able to clear the ice from the windshield. They then carried out an uneventful landing at Stony Rapids.