How cold is it? If you're going down to -5 C, I find that a set of half-finger leather weight lifting gloves with those black cotton magic gloves underneath work well. They're not water proof, though.

I've been wearing this combination of handwear for working on the trail with my friend. It's been hovering around 0. We're working a marshy kind of area (building suspended riding platforms). When the gloves get wet they're cold, but I find that they dried quickly.

For extra warmth you may dual up the magic gloves - they can be found at the dollar store - 2 pairs for a buck.