For Headset buy, HyperX Cloud Gaming Headset, for keyboards don't buy Razer and for mouses, just try all different kinds of mice, and buy the one with the best feel.
I'm going to be buying a new keyboard, mouse and headset soon and I am looking for the best company with good quality and a fair price.
Right now I'm using a Razer Mamba 2012, Razer BlackWidow Ultimate 2013 and a Razer Kraken Pro.
I've heard good things about logitech, but I thought I'd ask around before deciding anything.
For Headset buy, HyperX Cloud Gaming Headset, for keyboards don't buy Razer and for mouses, just try all different kinds of mice, and buy the one with the best feel.
Newegg or your local store if you even have one still.