Try a 7 1/2 watt 'ping-pong ball' size light bulb, about
3ft+ from the paper.  If this is too much light then apply
masking tape to the bulb.

If you need very sharp shadows then you need a point source.
Try a Mag-Lite [the fancy $$ aluminum ones] penlight.  The
reflector screws off, leaving sort of a candle affair with a
tiny little halogen lamp on the top.  The removed reflector then
doubles as a stand for the 'candle'.

If you are going to be doing a lot of this sort of work then
look on ebay for a 'nuArc point source printing lamp'.

You can also try using an electronic flash pointed upward, away from the
paper. I once did full body photograms of my kids when they were little
by having them lie on a long piece of enlarger paper cut from a roll.
If the flash is too bright cover it with diffuser or colored acetate.