In terms of black socks you really can't go wrong with Gold Toe. Great quality and I have them in all different styles ranging from thick winter socks to light summer socks. I sort of aquired a bunch because I used to need to wear black socks a lot for work so I essentially wear them all the time now.
I'm still looking for a good light sock since essentially out of my white socks I have a FEW pairs of Puma socks that are fineish but not amazing and then this pack of long white socks that I really hate wearing because they're really tight on my feet, plus they're long socks which I never really enjoy wearing if I don't have to. I may go sock shopping at some point but honestly I have enough (especially since I do laundry every week so I really don't go through all of my socks ever) to where I really don't need to go shopping., it would just be nice so I don't have to break out my thick socks every time I need to wear shoes.