It's not at Wincustomize. it's not on Deviantart. It is not at Pixtudio, his website. Themexp.org is currently down for upgrades. Only other two places I can think of are Neowin.net and Designtechnika.com
It is a windowblinds theme that was commissioned by NVidea. Treetog is the artist who created the theme. It is only available through purchase of certain NVidia products. Here is what is stated at Treetog's site www.pixtudio.com:
Author: Pixtudio, Greenreaper, PJPowell
Windowblinds skin created for NVidia Partners program special OEM pack. This skin is bundled with the GeForce cards produced by eVGA, ABIT, Jaton and others.
Thanks to GreenReaper and PJPowell who helped with the optimization.
You can get that theme and two others here BFG Technologies . You can install them even if you don't already have windowblinds because it will install an OEM type version of windowblinds if needed. If you already have windowblinds it will just install the three themes. They are pretty nice themes.