I use my dining room table. Open it as if I was going to insert the leaf, then I put a large piece of glass over the opening and a small bedside lamp underneath. Ta-da, instant light box.
My LQS offers a lightbox for sale, I can't remember the name brand, but holy cow it was $129 before the pandemic, who knows what they're going for now. Sorry, I'd rather use my homemade light box and spend that money on fabric, thread, and batting!