I guess it depends on the source whether you're adding music from tape, vinyl records or cd. Lots of people share their own music.

For the 1st 2, you'll need to hook up an output from your stereo to your computer's audio input. More ideally would be to have some type of pre-amplifier in-between which can control the sound levels of the input so there's no chance of the input level being too high. Line outputs from the stereo system are best, or even the headphone output. You'll probably need a pmg (6.5 mm) or 3.5 mm converter. Else an rca> 3.5 mm converter depending on what your stereo system offers. You should then open up an audio recording program on the computer & test the input on the loudest part of the music to make sure it doesn't go into the red on the input levels. An audio recording & editing softw that's free is Audacity: http://audacity.sourceforge.net/windows.php After recording you can split the songs & save as WAV. You may wish to apply filters to clean up any background noise & do some sound equalising to add back some quality. Then later convert those to mp3 or m4a.

If you are wanting to put cd to computer to share then you have a wide range of choices. Musicmatch for example or iTunes.

Most people prefer music that's been converted to 192 kkbs or higher in quality with 320 the highest. Hope this helps.