I always used to get cold feet, last year most of my winter riding was done starting at about 6:00am, so I spent time and money (quite a lot) getting it sorted.
I use:
1. Sidi Freeze boots (size 46) these are fleece lined ! Check out wiggle.co.uk for description and pictures, they are even black and yellow so go with club kit !
2. Conformable custom molded insoles
3. 2xPairs Assos Overshoes size III. The first is airblock for dry days and the other neoprene for the wet and/or really cold, the neoprene are much warmer.
4. Underneath that lot I only need to wear normal socks.
The point about not getting them wet is true, and also marco's point about tightness, the freeze boots have velcro straps which in my experience makes overtightening of the feet in shoes/boots much less likely than the normal sidi system.
I can't remember when I last had cold feet on the bike.
Toasty feet make a huge difference to your cycling pleasure.
Cheers, Huw