There are more videos on video.google.com

video.google.com has really improved lately. The collection has grown considerably. People interested in guitar music could for example search for Steve Vai, Zakk Wylde or "Crazy Guitar Tapping". There's a Zakk Wylde video that is around 56 min long called Zakk Wylde's instructional video (Pentatonic Hardcore). There is also a guy that plays a Mario tune on a guitar, search for "mario guitar".