The iPad is pretty big. I'd go for a full tripod unless you really want the walkingstick feature. A light tripod isn't that much harder to tote around than a good monopod, and can usually be used like a monopod with the legs collapsed. Thats what I do when I'm in a hurry to catch a shot; though only with my camera or iPhone.
I do have a monopod, and there are tricks that help make it more stable than just holding a pole; but when I get serious about taking photos I almost always regreat not taking a tripod instead.
I doubt you'll find a monopod or tripod designed specifically for the iPad. Instead look for monopods (or tripods) for traditional camera equipment, and tripod adaptor mounts for the iPad. Tripods and monopods typically use the same standard mounting hardware.
I can't recommend an iPad mount, but a search for iPad tripod adaptor turns up plenty of results.