I believe it is called loop stitching.

I think they're just a kid of staple...and tmac is right, I think they're called "loop stitching."

http://russellandhazel.stores.yahoo.net/fieldnotebook.html

http://bindingsupplies.co.uk/products/prod:Ring_King/prodID:P44E481709946C/
Apparently the "Ring King" looks like the most affordable way to do this, but they're still kind of expensive staplers.

Great. Thank you both :)