I don't think you posted this in the wrong place, you're just asking for something that's probably in rare supply if it exists at all; i.e. it's likely that no one knows of any open sourced games which use DirectX 11.
DirectX 11 is still very new compared to older versions, and because it only runs on newer hardware there are currently less potential players for DirectX 11 games than for DirectX 9 games for example. Also consider that games often take several years to develop, so those that are worth looking at were probably started using an older version, and any that are using DirectX 11 are probably still in their infant stages and aren't yet worth looking at.
//EDIT: I meant to continue this post originally but had a baby-related emergency to deal with! Back to it...
If you're willing to apply a little logic and imagination and the main thing you want to learn is how all of the parts go together, then perhaps you could look at the code from some open sourced games using different APIs? Just keep it mind that anywhere you see OpenGL/SFML/SDL/etc calls you would be using the DirectX equivalents instead.
You could try:
Does that help at all?
Edited by jbadams, 26 March 2014 - 02:24 AM.
Completed post with game suggestions.