I don't know of any software that directly edits MP3's, either on Win32 or Linux. What you need to do is decode to a wave file, run it through a sound editor to remove the offensive (?) part, and then re-encode it.
I'm certain there are Linux tools to decode and encode MP3's, although I don't know what's available in the way of sound editors. You might look around FreshMeat.net or something.
(Not to say that I approve of bowlderizing Pink Floyd, though...