Have read several posts elsewhere about this crinkle 'fabric'. This source seems to have 'some' experience by trying several things and this is what worked best so far for them:
http://www.joyshope.com/2009/05/baby...-tutorial.html
Another source that tried the clear plastic gift wrap was not satisfied with it since it pulled loose and bunched up after washing and did not crinkle. Another used tortilla chip bag, another used potato chip bags (well washed), and another used popcorn bag cellophane (microwave?). These seemed to be crinkly enough to please baby.
Good luck!!