Recently I have been studying Steve Bottorff's Sharpening Schoolvideo. As a change of pace, I watched an old favorite early this morning, Leonard Lee's Sharpening DVD. Leonard Lee is best known as the founder of Lee Valley and Veritas. He is also a practical and accomplished sharpener who teaches well.
This DVD was originally a VHS and made before Lee Valley carried Tormek. As such, it shows using basic water stones and simple procedures for sharpening chisels, planes, kitchen knives, scrapers and carving tools. While the material presented is not Tormek centric, the basic theory and techniques are an essential part of the background of a skilled Tormek user. I consider this DVD and the accompanying book as both essentials in my sharpening library. I would recommend they become part of your libraries as well.
Ken