You can buy the back seat from a wrecked car or junkyard. Or, you can pull out your existing seat and just not have one. Or #3, you can pull out your existing seat and fabricate some kind of hinge system. #2 is the cheapest/easiest.
2000 Contour SE 2.5L ATX - Toreador Red
2001 VW Golf GLS 2.0L MTX - Tornado Red
Buy my possessed VCR!!