For socks I use Cabelas Cool Max winter liners under Smart Wool hunting socks; as long as you don't do something stupid, like step in water deeper than your boot is high, (yeah, like most experience I acquired that one the hard way, though you'd think it wouldn't be really hard to figure out in advance) that combination works really well.
For clothing, after trying all kinds of stuff, I'm a great believer in Sleeping Indian wool, especially over EMS Bergelene (spelling is a guess)long underwear. They both move sweat so well that I managed to sweat up the back of my vest, but both the underwear and the outer wool stayed warm and dry.