How to replace ignition switch in 98 buick century?

I need to know how to replace ignition switch in 1998 Buick Century. If you could include pictures that would be even better.|||this could be very complex specially if you have airbags if i were you i pay a professional mechanic or locksmith to do it.|||the actual ignition switch or just the key %26amp; tumbler mechanism ?....this make,s a big difference.