This web camera may be slightly dated, but it has been my loyal companion for many great stream sessions.
Logitech C922 Pro Stream Webcam
Art streamers sometimes dip their toes into the gaming too, and the best way to connect your consoles to your computer to capture the footage on stream is this little gadget right here.
Elgato HD60 S+, External Capture Card
I used these at the beginning of my streaming adventures to give some atmosphere to the background of my webcam shot. They are cheap, and they provide a beautiful backlight.