I suggest you check the default community forum out at http://www.vbulletin.com. That's pretty much what you start out with when you use vBulletin version 3+. Zelaron's Synthesis theme has been customized entirely from the default layout of vBulletin 2, which in turn had to be remade once again for vBulletin 3. It's a lot of work to make a theme like this one.
"Stephen Wolfram is the creator of Mathematica and is widely regarded as the most important innovator in scientific and technical computing today." - Stephen Wolfram