PowerPoint isn't a 3D application and the drawing tools are limited. You'll
have much better luck using a 3D graphics program or an image editor with
extended capabilities, like Photoshop or Paint Shop Pro.
But, in PowerPoint you can give your circle a two color gradient fill with a
shading style of "From center" (color1 = the ligher color), add a shadow if you
want, and it'll sort of look three dimensional.
--
Sonia Coleman
Microsoft PowerPoint MVP Team
Autorun Software, Templates and Tutorials
http://www.soniacoleman.com