You get one stopover at the North American gateway - the last place your feet touch the ground in North America on your way out, or the first you touch on the way back. That's how it works.
Between North America and Europe, India, Asia, or Central / South America
One stopover is now permitted only at the North American "gateway" on awards between North America and another zone (in either direction). Note that multiple stopovers are permitted on oneworld awards, which have separate rules and mileage redemption rates.
See also:
http://www.flyertalk.com/forum/ameri...er-awards.html
Now... theoretically, many places are within North America that are not in the continental US. You just have to find a routing that puts you at one of those places immediately before you get to a place that is not within North America.
milevalue did a great summary of all the theoretically possible places:
http://milevalue.com/a-list-of-all-p...vantage-miles/