There are quite a number of sound files of mechanical music on the
Internet, if you know where to look.  The Musical Box Society
International (MBSI) is developing on its web site (http://www.mbsi.org/)
a virtual museum, with pictures and sound files of various musical
machines.  If anybody owns an interesting instrument and can provide
a picture and a sound recording of it, you could have your instrument
featured there.

The talented musician Rich Poor of San Diego, Calif., has recently
created a web site (http://infamousstudios.tripod.com/) where you can
hear many good MP3 files of his arrangements for Wurlitzer band organ.

My own web site (http://wurlitzer-rolls.com/) has a "Sounds" section
with more than 50 selections from Wurlitzer Style 165 band organ rolls
recorded in MP3 and RealAudio from various 165 band organs.

Additional recordings in RealAudio format made from the famous Glen
Echo Park Wurlitzer 165 are on this web page:
http://www.nps.gov/glec/caro/carmusic.htm

This page of John Tuttle's Player-Care web site has some MP3 and
RealAudio files of Craig Brougher's orchestrion "Spirit of
Independence": http://www.player-care.com/sofi5.html#samples

MIDI transcriptions of many of J. Lawrence Cook's Piano rolls are
collected on this web page:
http://musicforpianos.com/J.Lawrence%20Cook.htm

Terry Smythe has scanned more than two thousand piano rolls into
MIDI form and offers them in batches on this page of his web site:
http://members.shaw.ca/smythe/archive.htm

There is some music on the Stinson Band Organ Company web site.  Here
is the URL for its home page:  http://stinsonbandorgans.com/

This web site has hundreds of MIDI's and, while most are not recorded
from mechanical music machines, there is some interesting old-time
music there: http://www.mybonbon.com/

This page lists the jazz and stride piano rolls arranged by John
Farrell and offers MIDI files of many of them:
http://homepages.tesco.net/~stridepiano/website.htm

These URLs should get you started, and I'm sure there are more that
other MMD readers will point you to.

Matthew Caulfield (Irondequoit, N.Y.)