It is pretty reasy to find free midi files on the net however if you have
still some problems to get some here is some link to listen for free
some midi files, remember that these files have an owner
http://pop.mididb.com/
http://mgag.creationsmedimage.com/Musique/70_s_diverse/
http://meltingpot.fortunecity.com/cecilian/557/pop_r.htm
http://www.calpoly.edu/~cpasilla/music/mindex.html
http://www.fillies.com/midi/jukebox.htm