Hobby Lobby, Joanne Fabrics, etc... and you don't mess with the tabs etc from the pep files, you just stencil, cut and glue from what I can tell. I know it's great for costumes like Captain America, etc... Though in my opinion I would just use EVA for costumes that have a rubber type looks like Batman, or the Cap, but stick to the card/fiberglass/bondo method for hard armor. But again it depends on your budget, (how much your wife will let you spend lol), time you want to put into the build, etc... I hear you can do a full suit for about 48 bucks of EVA. Also you can combine the different types in one costume as well. Like if a pience needs to bend some, or give, example the iron man neck piece would be best made from foam then the other method. Also EVA foam is a great way to pad your armor to get the proper fit on loose pieces, like bicep Trooper piece. Best to be creative and share with others what you find works best ^_^