My brand new key wont turn the ignition.

Maybe. If you have two keys that are already programmed into the computer you can add a third. If not, you'll need a very good locksmith or the dealer with the scanner to change the computer settings.

sounds like you broke the ignition more sacific one of the contacts in the ignition. if it just turns over but wont fire there is no power to the ignition system. you need a new one.

I think it has some thing to with a relay maybe.

pull coil wire off safely or call fire Dept.

Yes it is, but just having the key near the ignition is enough to start the car. If you can turn the ignition with the broken key, hold the broken part in your hand and see if it will start. Hopefully the chip isn't damaged. I know that when GM keys are replaced, they glue the old key under the dash to make it work. Hope this helps.

disconnect the battery for 3 mins

Not an exact solution, but perhaps information that might lead to one.

1.Replaced the tumblers? I believe I would replace the entire ignition switch this time. It's my belief that the body of the ignition switch is worn inside, and will keep damaging the tumblers.

2.Do you have a tilt steering wheel? It's best to keep the steering column in straight line when starting the car, then tilt the wheel to where you want, after the car is started. When the steering column is in a tilted position, it puts undue strain on the ignition key switch, and the mechanism the ignition key switch operates, on GM vehicles.

This mechanism, consists of a half moon gear on the ignition key switch, that turns inside a 'Planetary' gear. I used the term 'Planetary', as the gear shape is hard to describe. It resembles an oblong loop, shaped like the number 9, with gear teeth on the inside bottom of the loop. This 'Loop' rotates, when the gear teeth of the ignition key switch, engage the teeth on the loop, and pushes a rod, or retracts the rod. The rod goes down the side of your steering column, and turns on, or turns off an ignition switch, located at the bottom left side of the steering column.

Having the steering wheel tilted, puts a strain on the ignition key switch internals, the oblong loop can break, and/or gear teeth can be stripped off.

take the key back to the dealership get them to sort it out

no it sounds like the ignition clinder is broken or worn down inside either that or maybe the key itself. get a new key made (local hardware store) and try that one if that doesnt work im afraid that you may need a new key and tumbler