One of XtremeMac's first new cases for the new third-generation iPad is its Vintage Sleeve ($50). Although it has a pretty basic sleeve setup, the materials -- waxed canvas, real-feeling faux leather, and a metal snap -- are all quite nice. A tab is found inside of the front cover so that you can easily pull the tablet out of the case. There's also a loop at the top left corner that can be used as a handle, and the flap stops just short of covering…