I've published an illustrated step-by-step skin retouching tutorial in my blog.
The article focuses on how to clean skin effects, and how to do edits like a nose form. Skin smoothing technique will be described separately.
Remark: It is not a video - it is printed text with pictures :)
Your feedback is welcome - either here or under the main article at http://miklav.blogspot.com/2008/07/beginners-skin-retouching-tutorial.html