Mainerider: On my hands I wear PearlIzium gloves that look like ski gloves and are nice and toasty. For my feet I wear thin or medium weight wool socks and mountain style clipless shoes. The shoes are a bit meshy, so I also have Burley shoe covers, but I haven't used them yet. Strangely enough, I feel most cold from my knees to my elbows. It seems more common to be cold at your extremities, but for me it's my core.

CorsairMac: I don't always eat before the ride. Sometimes I ate a cup of oatmeal before the ride, and sometimes I would pack it with me and eat it when I got to work. I would usually eat something in the afternoon, a couple of hours before leaving work. I did feel like I wasn't getting enough protein, so that could be part of the problem. I also think that I wasn't drinking enough during the ride. Because I wore my backpack, I didn't have my Camelbak with me to suck on, and I don't have an easy-to-drink-from water bottle on my bike. I ended up only drinking at stop lights. Also, I bet if I warmed up the water before I leave I would be more tempted to drink and it would help warm me up inside.

I think you're right that I'll just have to play around with it. It's definitely worth it, but I just wish it weren't so cold when I get the combinations wrong!

I think another part of my tiredness was that I also started taking a martial arts class, which was an entirely new form of exercise for my body. I kept telling myself that I should be fine, but perhaps I was tired because my body was busy healing from class and from falling off (or more like it, on) my bike (still getting used to the clipless ).

As for other exercise: before I started doing the bike commuting, I was mostly running and weight lifting. I would run about twice a week and lift weights two or three times a week. I stopped doing both of those in order to have enough energy for biking and martial arts. I've stopped the martial arts class, so now all I have is biking, and then once I increase the biking, or at least feel like I have enough energy, I'll pick up weight training again.

So, it sounds like I just need to play around with different layer combinations and learn what works for me. I'll take a look at the Sugoi firwall tights. I'll drink more water and try to eat closer to when I bike. Not taking martial arts should help.

Thanks for the help and advice. More is always welcome : ).
Cheers!