Hi Clam -
I can help you with this one, as I've just done the fix.
Basically, the weight of the airbag is supported by four rubber septa (I'm sure there's a better word for this...) with a metal sleeve in the middle all supported by a metal frame. Over time the rubber septa degrade/split/fail allowing the frame to hit the horn contacts and giving you the beeps every time you hit a bump (very embarrassing!). There are two torx screws accessible from the back of the steering wheel that will release the airbag and allow access to the metal frame.
Be sure to disconnect the battery before starting and situate the steering wheel where you want it and remove the key from the ignition. Loosen the screws in the back - they're in there with Loctite, so it takes a little force. The airbag pulls right off and can be disconnected by just popping up the yellow connector at the airbag. Now, you will see four large hex nuts in each corner of the steering wheel. The rubber septa are underneath these hex nuts. Remove the four hex nuts, and the metal frame will come loose. Don't lose the two torx screws that will come off with the frame. Those are the screws that hold on the airbag.
Now the fix. If you search here and on the various fora, you will see several different fixes that come in two basic varieties: one: make a new septa with various washers, garden hose pieces, etc., or, two: just fill in the gaps with a high-temp silicone. (This will all make complete sense once you get that frame off and actually see what the septa look like and how it works).
I went with the fill-in-the gaps option and just filled both sides of the septa with "high-temp red RTV silicone gasket maker" that I got at the local auto parts store for about $7, leaving the old bushing completely in place and just filling the cavity with the silicone. It has to set up for 24-hours. Reverse the process above and you're done.
I did this fix about two weeks ago, and so far, no beeps. Life is good.
Now, if I could've just gotten that #^&U^ing overflow tank out...
Amy