He means the images in the tutorial post on wowace.
Yes, they are attachments to the post, so, it may be that you need to log in, I'm not sure. They show up fine for me. There are probably other tutorials on the web as well, I'm sure.
There are three rules for WoW graphics:
1. The file must be in .tga or .blp format
2. The file must have an alpha layer (this would mean 32-bit .tga, not 24-bit)
3. The dimensions of the image must be a power of 2
If you're more comfortable working with .pngs (which have a transparent/alpha layer by default) then you can convert them to .blp using
http://www.wowinterface.com/download...7-BLP2PNG.html