The skins below were made for Winanp Player, a freeware by Nullsoft.
Here is how to use them : click on the skin of your choice, it will download automatically. Then click on the small sign on the upper left corner of your Winamp window, then on skins => skins browser => set skins directory.
Look in there for the file where the skin should be. Then just select it and your Winamp Player will have a new skin. Warning : do not unzip the file!