Many folks have been asking for the Master Page that I use in my demos. Here it is with the images that you need. There is a file called internal.master for the master page and then a folder called internal and then a folder called images under it. You'll need to post these to your Master Page galley for your SharePoint site and then make your site use the new Master Page.
If there are any issues that you have trying to use this, just let me know.