you will need to get it towed to a tranny shop, your tranny is baked (needs to be replaced/rebuilt)

Is your shifter stuck or the transmission?

if its just the shifter that won't move there could be a problem with your ignition switch, if its automatic, or the shift interlock mechanism from the brake pedal.  check to see if there is a small hole or a place for the key to insert either the key or a small slotted screwdriver and push down and try it that way.  that will make sure that aspect works properly.  

or the cable could have freyed and seized up .

if its standard that would be a bad thing if it just happened yesterday or something, and it worked fine before.

It's probly your neutral safty switch.