Merino. I can't stress it enough. Merino.

Now what brand of merino depends upon how scared you are of little tiny eensy needles.

My first favorite is Koigu Painter's Pallette Premium Merino. But I'd save that for after you have knitted a sock. It's some pretty special stuff.

Running a close second is Lorna's Laces Shepherd Sock. Fantastic colors! Great hand! Merino and nylon! It's skinny though. You'll likely use size 2 or three needles. They have most of the same colors in Shepherd Sport which will also make a great sock.

Other faves:
Artyarns Supermerino (sport weight) or Ultramerino (fingering weight)

Enjoy! Sock knitting is the business!

My first (successful) socks were on Regia silk. They're to die for. Softer with each washing. I can't wait until they're clean again and I can wear them again! :)

Merino superwash!!! Easy to knit with, and machine wash, and dryable!

I second (third?) merino wool. Wool is amazingly cool and aborbant on your feet and you will get so much use out of the socks (they're my favorite for the 100+ heat of Tucson--so much cooler than cotton!). Merino is as soft as wool comes. Cotton yarn often feels rough on your feet, like walking on dish clothes. I know cotton sounds good, since all your commercial socks are made from it, but the thread they machine knit with is so much thinner than anything you'll be handknitting. Acrylic doesn't wick, so I'd stay away.

However, I strongly recommend buy wool with nylon blended in. It will last so much longer (I've had my blended socks for years, while the plain wool only lasted months). Some people carry a nylon thread along with their wool. I haven't tried that yet, as I've heard that the nylon thread can bite into the wool, cutting it sooner (but, it does have the advantage over plain wool that the remaining nylon thread makes darning easier). As for brands, I love Lorna's Laces, but it is pricey. Basically, any merino w/ nylon in a color you fancy will be perfect.

Company: Lorna's Laces

Weight/type: Shepard's Sock

Tons of to die for colors...

I like to buy them through The Loopy Ewe - link below
www.theloopyewe.com/

Another good one is
Socks that Rock by Blue Moon Fiber Arts - link below
www.bluemoonfiberarts.com/

Okay now you've got me drooling....