I think for riding in cold weather, good base layers are a must. The craft base layers are very good for cycling. Performance and local shops usually carry craft. Getting a sleeveless and long sleeve base layer is a good item to add to your winter collection.. The under armour cold weather base layers work well too, they are more of a compression fit.

I use knickers down to 50 and tights for 30-40 degree weather. I personally have some older team issue jackets that I wear when it is real cold. Sinchi Fleece jackets are windproof and good down to 30 degree weather.

If you can wear wool, wool socks and jerseys are still a solid bet for keeping warm when the weather gets cooler.