Car runs has new starter new alternator new battery and now all power is out. Mechanics run and car drives but power windows lights headlights breaklights are all out. Cant even get the key out of the ignition because there is a lock on it. Please if you have any idea please help.

Check you fuses....and the positive battery terminal and it's multiple connections...those terminal usually wear out, corrode or are the issue...Cut terminal off and use bolt type spade connectors straight to the battery terminal....

Sounds like a popped fuse affecting windows, brakelights and headlights. Also check fuseible link and battery terminals ike CMax had mentioned. As far as your key locked in the ignition the button on the steering column should release the key not sure a fuse out would cause the key to be stuck in the ignition. If you have access to a FSM check the electrical section to see which fuse or fuses are connected to the headlights, tail lights and windows.

Yep just push the button turn the key and pull the key out....Like Magic!!!!