Very good tutorial for anyone packing a machine. If you can't find a source for free foam sheets or styrofoam, you can get foam insulation board at your local hardware store. Just let your buyer know in advance that packing these things is a little more involved than just throwing them in a box and that it will cost extra. If they're interested in the machine enough to pay shipping, they probably won't mind a few dollars more for it to arrive safely.
Rodney