Klim Adrenaline GTX, or if you really have naturally cold feet, get the Klim Arctic GTX boots. It has either almost double or exactly double the amount of thinsulate in the boot over the Adrenalines.
I just bought a pair of Adrenalines and like them. Just have to use good wool socks for moisture wicking.
If you're looking for cheap but warm, try the bunny boots:
http://www.bunnyboots.com/
They use bunny boots a lot in the iron dog race because of the waterproof insulation. If they don't have waterproof insulation, they're required to carry an extra pair of liners or boots or something like that. So using the bunny boots allows them to safe weight and space on their sleds. Bunny boots apparently don't always fit really well under the footwells though, and aren't super durable.