Music editing can be a complicated and elaborate business. However, there are several aspects of music editing which do not require an expert training. While there are several commercial music editors in the market, if you are not looking for stuff too fancy, you can rely on Audacity – a free open-source music editing software. You can download it from http://audacity.sourceforge.net/download/

What do you get from Audacity – the free music editing software?

You can work on audio and stereo tracks for -

Music Editing

• Cut, Copy, Paste, and Delete tracks or portions of tracks.
• Unlimited Undo and Redo
• Editing and mixing of an unlimited number of tracks.
• Zooming in to edit individual sample points.

Adding Effects

• Noise reduction
• Time Shifting
• Changing speed, pitch or tempo
• Filtering using equalizer or FFT
• Employing pre-built effects (eg amplify, fade-in, fade-out, echo)

please note that some menu options are not available when you are playing a track. Click the 'STOP' button before using the effects.

Import and Export Audio Files

• It can import and export wav, mp3, aiff and ogg vorbis. However for mp3 support, you need to download LAME mp3 encoder
  

Recording

• You can record music from the appropriate hardware (microphone, line-in, CD-player, sound card). If you can listen to a music in your computer, you can record it too. Use ‘Wave Out Mix’ as your source if you want to record what you are listening to.

It has brilliant sound quality for both recorded and edited/exported music files. You can further control the quality by altering the bit formats and sampling rates. For the more tech-savvy people, it supports third party plug-ins and you can write your own. And yes, it comes for Windows, Mac OS and Linux/Unix. You can download it from http://audacity.sourceforge.net/download/