Not in the US, can't pre-order an iPad via store.apple.com/us, willing to travel by plane, train, or automobile to the closest Apple Retail Store on April 3? Then reserve your iPad for pick-up now and be sure get one when you get there!
You'll need an Apple Online Store ID to reserve one, but my Canadian Apple Online Store ID worked just fine. If yours works too, let us know in the comments!
Note: If you buy an iPad from the US, you'll likely need to have to go back to the US for any warrties