Well I would need more details... I can't really understand where is the problem... just download the icon from the site, unzip it, and import it into the editor. After, close the editor and re-open your map. And the icon should be working...
GIP image? Well I didn't understand that quite well.... I can't see whats your problem; to make an icon just use the WC3viewer to convert the format of the icon you extracted to .tga, then you edit it on photoshop, and when you're done, convert it again to .blp! What's so difficult?