How do I edit .wav files?

[Jaco Swart]

Which utility can I use to edit .wav files before I burn them to a music 
CD? All I really want to accomplish, is to add some silence to the end 
of certain tracks (at the end of a symphony, you really want 30 to 60 
seconds of silence before the next piece starts).

I need a solution for both RH7.3 and 'Drake9.1

thanks!
Jaco