- Home improvement stores: Home improvement stores like Lowe's, Home Depot, or Ace Hardware typically carry polystyrene sheets in various sizes and thicknesses.
- Craft stores: Craft stores like Michaels, Hobby Lobby, or Jo-Ann Fabrics may have a selection of polystyrene sheets, though they may be smaller or more decorative in nature.
- Online retailers: Online retailers such as Amazon or eBay offer a wide variety of polystyrene sheets in different sizes, thicknesses, and colors.
- Plastic supply stores: If you're looking for larger quantities or specialized types of polystyrene sheets, you might consider contacting a plastics supply store in your area.
It's always a good idea to check the availability and specific options at your local stores or online before making a purchase.