Foraging can be expensive. Quality, forager-specific books aren’t cheap, but are essential, as they can save your life. You’re not likely to find good foraging books used, but most of the other gear you need can be picked up for a few dollars — if you’re patient, and keep your eye out!
A good quality backpack is one of the most essential foraging tools. It’s the easiest way to carry your finds through the woods, over rough terrain. It should have comfortable straps, ideally padded, and be a good size for your body. Lots of pockets and pouches for organization are also a plus.