if your dont mind paying a little extra a really good place to find them would be lowes they have a bigger selection then home depot and way better quality
You could find a good selection of loft hatches constructed of both wood and metal at your local home improvement center. The types you find here would be of a standard to fit in most homes.
You can find loft hatches at just about any hardware store or home improvement store, generally in the hardware section. Keep in mind the hatches come in many different sizes, shapes, and materials.
