they might seem expensive, but as long as you get the ones made by schwalbe or nokian, they'll last at least 3 winters, 5 at most.
If the road is going to be ploughed, but occasionally icy, then I'd say the schwalbe marathon winter would be the best choice.
the list here should help you:
http://www.komponentix.de/onlineshop...nterreifen.htm
Eis = ice
Schnee = snow
Matsch = mud
Asphalt = asphalt
sehr gut = very good
gut = good
befried = decent