The HolyGoat speaks truth! Pretty much everything I would recommend. I prefer wool for almost all my outdoor excursions. I recently got a Mackinaw wool pullover from www.gfredasbell.com that is an absolutely amazing piece of kit. I find myself quite comfortable into the teens with just a wicking t-shirt, light insulating layer (I've been using a super light fleece from Columbia... thinner than "100" weight), and the pull-over. Top it off with a wool watch cap and leather insulated mittens. I wear a "mid-weight" merino longjohns from Cabela's. They seem more "light-weight" to me, but they do the job quite well. I stay perfectly warm while hiking.
What type of wicking t-shirt (undershirt) do you wear?
I think I can find a decent regular shirt to go over it, but what type of material would you recommend? A Merino Wool-type of long sleeve shirt underneath your jacket/coat?
Do you wear underwear under your longjohns? I always do, so I'd like to get some good underwear for cold, outdoor weather along with undershirts. I think I have a handle on socks....super thin wool-type sock liner and then a wool outer-sock.