Do what I did, just use cheapo software for creating icons. They usually let you extract icons from .exe and .dll files. Or you could do it the hard way: set your desktop to a pure color, take a screenshot with Paint Shop Pro or the Print Screen button, crop that image to 32x32 around the icon, save it temporarily, use an icon program to create a new icon and be sure to take that "pure color" you used before and use it as your transparency color. Finally, export the image as a new icon. I'd use the former method, but this latter one can be useful. I made my own WA2 icon by taking the WA3 one and changing the colors to match those on Shoutcast.com so I could have a version of WA2 LITE dedicated to streaming audio with a specific icon for it on the desktop to differentiate between my normal WA2 FULL.
The problem is is only works for shortcuts. You obviously can't change the WA2 system tray or taskbar icons. Just your shortcuts. I have my desktop, Star Menu root, and Start Menu nested WA2 icons using the cleaner WA3 default shortcut icon.
To change your shortcuts, save the ripped icons in your WA2 folder and for any shortcuts you have to WA2, edit them (right-click, choose properties, select change icon) so they use your new icon instead of the ones embedded into the WA2 EXE.