um, I will have to say that that tutorial will not do for that style. I would show you a link to a tutorial, but I cant find it anymore. Just make a white circle, duplicate it three times, blur-Gaussian one really big (like20-50 depending on the size.) The next one you should blur it again (select the layer then ctrl-alt-f) and put the blur at around half of the first one. I got something like what you sound like you are looking for. For added realism, add a green inner glow at 10% opacity.
http://forums.biorust.com/photopost/...dium/sunny.jpg