Where can I get a replacement steering wheel ?

Are you trying to replace the wheel with a fancy aftermarket one, or is your one damaged?
If this vehicle has the SRS steering wheel bag, and you do not know what you are doing, I would not try this at home.
if you feel that you need to, check YouTube videos and have a good look at the explosion that will occur if you stuff up.
A non SRS bag steering, start at the rear of the wheel and undo the two screws recessed into the steering wheel spokes that hold the centre boss on. After that it should be self explanatory, after undoing the big nut you may have to jiggle the wheel quite hard to unseat the boss off the splines. Try to have your wheels in the straight ahead position so that you don't end up with the spokes at a funny angle when you put the replacement wheel back on.

check fuses check to see if the other buttons on the steering wheel work if there are any (not the ones on the steering column if there are any buttons on the steering wheel try them) if all fuses are good and nothing on the steering wheel works there is a plastic disc between the steering wheel and the steering column this makes the electronic connection the part may run between 50-200 dollars depending on the car its a pain if you dont know how to replace it so you need a mechanic thats going to dig in your pocket sometimes its better to just go without a horn and just use your finger good luck

The steering shaft has splines that allow the steering wheel to be positioned correctly with the front wheels.
Try tapping behind the streering wheel with a hammer to loosen so you can pull the steering wheel off.
If this does not work then you need a wheel puller to pull the steering wheel off the steering shaft.

Steering Wheel Control Switch Assembly Replacement Removal Procedure

1. Remove the steering wheel. Refer to Steering Wheel Replacement .
   
   
   
2. Remove the horn switch from the steering wheel.
   
   
   
3. Remove the steering wheel shroud retaining screws from the back of the steering wheel.
4. Remove the steering wheel shroud from the steering wheel.
   
   
   
5. Remove the steering wheel control switch mounting screws.
   
   
   
6. Disconnect the steering wheel control switch (2) electrical connector (1).
   
   
   
7. Remove the steering wheel control switch from the steering wheel.

Steering Wheel Replacement Tools Required J 1859-A Steering Wheel Puller
Removal Procedure

1. Disable the supplemental inflatable restraint (SIR) system. Refer to Disabling the SIR System in SIR.
2. Remove the inflator module. Refer to Inflatable Restraint Steering Wheel Module Replacement in SIR.
3. Remove the horn switch. Refer to Horn Switch Replacement - On Vehicle .
4. Make an alignment mark in order to note the relationship of the steering wheel to the steering shaft.
5. Remove the steering wheel nut.
   
   
   
6. Remove the steering wheel, using the J 1859-A .

Installation Procedure

If you had the clockspring on wrong and turned it, it is damaged now and needs to be replaced. Remove it and put the steering wheel on and turn to confirm. You need to disassemble and inspect.

Have you tried turning the steering wheel while turning the key? I know you said it's locked, but they usually have a little play in them, sometimes when it's turned as far as the lock will let it the ignition will be put in a bind. If that doesn't help the only other option I can think of would be to replace the ignition set yourself, you'll get new keys and save yourself a trip to the dealer.

try turning steering wheel a bit, or move shifter up past park. Otherwise ignition may have a broken or stuck pin and will need to be replaced.

if you disconnect the battery and let it sit awhile this will disable the airbag.

Disconnect negative battery cable. Locate airbag retentions on back of steering wheel. Unbolt or unclip retention devices, and release airbag. Then: Unplug airbag electrical connector. Remove nut or bolt in center of steering wheel with pneumatic impact wrench if necessary . Using appropriate steering wheel removal tool kit, carefully remove steering wheel, paying attention to associated wires, etc. Unplug anything not accompanying wheel, or that is in the way. Pay close attention to any rods, or contact pieces associated with the horn button(s.) Replace these upon reinstall. Reverse order to install including tightening center bolt to 35-55 ft-lbs. If this is your first stg wheel removal, try an old chevy, preferrably someone else's! If inexperienced, don't risk bruising your favorite Bimmer!!! Hope this helps you make your decision. Tater Todd

I hooked the wrong power supply to my wheel.Pretty dumb I know.Is there a protection diode or something I can replace or do I have to figure this out on my own?
Jim