Be sure to look into your rights with a design when you "can't remember" where it's from! otherwise you may run into copyright issues if you plan on using it.
I would personally choose a different font and work a little more on the right navigation section. As well as this, the "Content Header" is a little bit hard to read with the textured background, a little more contrast? and perhaps a better way of distinguishing it from regular paragraph text.
The overall layout is nice though, I like the logo and lighting effects at the top. If you need some filler text for mock layouts, http://www.lipsum.com is a nice resource.