The Park tool will allow you to get the rotor near perfect. Before using the Park tool I was able to move gradual rotor warp with my hands, however that method left a far from perfect result. I have used a small adjustable wrench with less than terrific results, however it is possible to get a warp out enough to reduce, but not eliminate that rotor zing as it passes through the pads.
If shipping the bike, remove the rotors and flat pack between something stiff.