if the paper is metallised, then radar can track it
Aim for the centre of the USA, and have a few AWACS ready...
And a reward for delivery to the local Post Office.
Anyway, why launch just one, when you could drop a whole fleet of origami cranes or paper planes, or sailor's hats and track the wind patterns of a whole continent, like the famous "Rubber Duck" fleet... http://oceannews.blogspot.com/2007/07/plastic-duck-armada-is-heading-for.html