Where can I locate themes for VS2012

Yes, luckily you can revert the Visual Studio 2012 ALL CAPS menus to normal menus by hacking the registry:

1. Launch regedit and navigate to
   HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\11.0\General
2. Create a DWORD value named SuppressUppercaseConversion with value 1.

NOTE: As explained in the answer pointed by Yahoo Serious, the VisualStudio part on the registry key name should be changed to VSWinExpress for Visual Studio Express, and to VWDExpress for Visual Studio Express for Web.

UPDATE:

I have applied this hack in another machine and at first it did not work. It turned out that I had selected the key name from this response by double clicking it, then copied it, then pasted it in regedit. Well, by doing so I had inadvertently created the key with a trailing space in the name! And hence it did not work.

So, if you apply this hack and it seems to not work, ensure that there are no trailing spaces in the key name.