Recently I have really been enjoying (and learning) watching videos by "This Old Tony". He gives a mix of knowledge, humor, and excellent video production.
My friend Alan thinks highly of "Blondihacks". She has a big collection of videos.
And more: These guys are classics:
Two other sources have recently come to my attention. First is Stefan Gotteswinter who is a professional machinist, yet does videos of his work at home in his home shop. Second is "Edge Precision" who (like Abom79) is doing gigantic work in a professional shop.
The clickspring videos are spectacular, some of the best produced videos on Youtube.
Tom's home page / tom@mmto.org