bestskinsever (and xtremeguard if I need something cheaper or need it for a device the bestskinsever don't support..which is MOST of the time) are my goto for polyurethane skins. I recently got a nintendo 3ds that I skinned all up. I was originally only going to do the touchscreen but decided what the hell.. the full body was a dollar more.
That said... for my ipad I went with a tempered glass. The rubber feel of the polyurethane skins can get to you after awhile and you just can't beat the feeling of glass if you can help it. With that said, I have no single source. I mainly just find a china supplier on ebay that passes my smell test. I looked up my order list and see the one I got was "[Scratch Terminator] Anker® Tempered-Glass Screen Protector for iPad Mini/Mini2". It was an excellent protector that had wonderfully beveled edges, cost $13. My phones protector didnt have the beveled edges and feels harsh, but luckily the commuter case keeps your fingers away from the edge.