the one button for the radio isnt working, how do I get it out of the steering wheel and where do I get a replacement

You can't just replace the bulbs unfortunately. Its the whole switch or nothing.

I think you can push them out from the back somehow, but I just used one of the blades on a multi-tool I had to pry them out. Just worked it side to side, and eventually it came loose. I've had to replace all of mine, 3 down, and the one on the upper left spoke finally went lights out, so when I get that done, all 4 will be new.
Only other thing I know, is that the leads are really short. So, don't pull too hard, and make sure you have the replacement handy, and some needle nose pliers to pull the connector back out of the socket if you drop it back down in there.
Only place I know of, is straight from the dealer. No one else sells them new, and if you get salvage vehicle ones, you have no idea if they will light or work for long. I can't remember prices, but none of them were over $50 from the dealer. I just replaced them one at a time. You will probably need to have the VIN so they can pull up the build, and get you the right ones, and the right color for your car interior.
Not sure which ones you have on a 00, but some have only the cruise, some have radio control, some have radio and heater controls. All should be the same R&R though.