The key to the lock on my hatch broke off in it the first day I got the car an it was the only one I had. My question is, if i find a way to knock the lock out, will the hatch still stay down and would I be able to close and open it? And does anyone know how I could break the lock out without breaking anything else?

On the 86 and newer Camaro you can take the rear lock out and the hatch will still work, you'd just need to use the interior power release or something to turn the release cable that snaps on the end of the key to open it. To take the lock cylinder out you have to remove the plastic panel on the inside, snap the plastic release cable off of the end of the lock cylinder, then remove the metal retaining clip and the whole lock assembly can slide out.

Not sure how different it is on the Firebirds. I just took mine out a few days ago so its still fresh on my mind!

The cover over the lock that you see from the outside holds all the guts back in the lock, if you get that off you might be able to pull your broken key out. You'd just have to find a new external lock cover because you'll wreck the old one taking it off.

the power release dont work but should i still be able to remove the interior an knock it out?

Kinda cept for two screw on the top for the contacts that you won't be able to get to.

call a lock smith, they will fish out the broken bit and make a new key from it.