I want to build a Darth Vader helmet/mask. Sculpting is no problem, neither is building the vacuum former, but every web link I have found just tells me what kind of plastic to use, not where to buy it.
Google your own address then Map then Search Nearby and Plastics - Sheet. This should give you places that will sell you many kinds of plastics and will cut down from full sheets (which are 4x8 ft in US) Call them and ask about types and cost. Some specialize. In Dallas Texas, Regal Plastics is one such.
