1. Go to STP and sign up for the DealFlyer e-mail:
http://www.sierratradingpost.com/dealflyer/
2. Wait to get your e-mail with the 30% off eCoupon.
3. Click on the coupon to go to the STP site and search for the SmartWool and Icebreaker brands.
4. Check out the merino wool base layers and socks from those two brands and read the customer reviews. STP sells items on closeout, so the available sizes and styles constantly change. If they don't have what you're looking for the first time then keep checking each time you get an eCoupon to see if they have what you need in their inventory. I bought all of my current merino wool items (base layers, socks, sweaters) from STP and saved big $'s in the process by using the eCoupons. I have a mix of Icebreaker and SmartWool merino items and the quality is excellent and there is no stink factor like with UA or other synthetics.
STP rotates the eCoupons frequently. One week it's an extra 30% off your order. The next week it's an extra 25% off. Eventually they will send you an eCoupon for an extra 35% off + free shipping on orders over $100. That is when I pounce. They have lots of other quality items, too. I got some nice ScentLok items there for well over 50% off what they cost in retail stores.