Skinning avatar

I have been using a prebuilt avatar skin rather than fiddling with the basic avatar editor but have an interest in creating my own, unique skin. Can anyone point me to a forum or provide pointers on how skinning is actually done? I have downloaded a head and torso template but have NO clue as to how to deal with it: How does one change the shape? Once one has created such a skin, how is it put into SL and used? I am interested in something akin to a "furry" skin and use GIMP as a photo-editor (essentially like Photoshop).

Unfortunately, the skin I am using, though grossly similar to what I would like to create myself, is uneditable so I cannot take a good look at it to determine how it was done...are there skins out there that CAN be looked at and even edited? It would help in learning how to skin in general.

Robin Sojourner has some texturizing tutorials at her shop site, including a tutorial about skins.

Look her up in search, I think the tutorials are located just outside her shop (which is the first of the picks in her profile).