Although you might find it strange, in GNU/Linux there are excellent multimedia editing programs.
Proof of this is Audacity, which thanks to its increase in functionalities, has become a very complete application used to create and edit audio files. Furthermore, it's a completely free software.
Audacity lets you edit quite a large number of audio formats. These include AUP, AIF, WAV, AU, MP3, MPG, MPEG, MP2, MPA, OGG, FLAC or LOF.
This makes operations like recording audio clips, digitalizing sounds, cuts and compositions or applying effects to different audio sounds very easy tasks.