From a netfriend:

CDs, DVDs, MP3s??????? Why?

Have a look for the songs in MIDI format. MIDIs can be played on a computer, using most sound players, through a sound card into a sound system. They are very compact music file formats, too.

Search for tunes in MIDI format using your favourite browser.

Examples:

http://www.cyberhymnal.org (Hymn tunes)

http://www.wc4.org/midi_files.htm (Lots of everything!)

http://www.mountainretreatorg.net/midi.html (Some modern tunes)

BE WARNED: The implementation of the MIDI format varies wildly. Some sound lovely, others awfully bad. This is a result of the file being ‘written’ for specific sound production (e.g. by a piano, organ, multi-instrument sounds, etc)…. or…. ‘generic’ coding that normally comes out as either a wheezy organ sound or a honkitonk piano.

Alternatively, someone who knows what they are doing (not necessarily a musician) could readily create/copy the MIDI files using simple music software. It’s also possible to use some ‘keyboards’ to record MIDI to 3.5″ disk or output this to a computer through an appropriate sound card and program.