AI Skins--List of Available Choices
From The DarkMod Wiki
Now that Dark Radiant includes a skin chooser for AI, an illustrated list is no longer necessary. Simply select the AI entity and add a new property, "skin" "0". Then select that property. A "Choose Skin" button will appear, and if you click that you will be able to browse all the skins available for that model.
See also Heads Available for AI.