I've used it for years to make stencils and masks for painting onto fabric. I buy it at the grocery store, around here it's available pretty much everywhere that you can buy stuff like waxed paper. One box does go a long way, I've been using it for probably 10 years and I think I'm only on my 3rd box.
I also second the recommendation for parchment paper. I believe it's silicone coated so it's heat resistant and pretty much nothing sticks to it (like fusible web) so it's great as a pressing "cloth". Weirdly, I even cook with it!