Preheat the oven to 325°F and butter a 15x10x2-inch glass baking dish. Bake the bread pieces on 2 large rimmed baking sheets for about 20 minutes, tossing occasionally, or until lightly toasted.
Sauté the sausages in a large sauté pan over high heat until cooked through, breaking them up into large bite-size pieces with a spoon, about 10 minutes. Using a slotted spoon, transfer the sausages to a large bowl.
Add the toasted bread and toss to combine well. Melt the butter in the same sauté pan with the pan drippings. Add the onion, celery and garlic to the pan and sauté for 12 minutes or until the onions are very tender.
Add the sage and sauté for 2 minutes or until the sage is dark green. Stir the onion mixture into the stuffing. Season to taste with salt and pepper. Toss the stuffing with the eggs to combine well. Add enough broth to moisten the stuffing slightly.
Transfer the stuffing to the prepared dish. Cover with foil. The stuffing can be prepared up to this point 8 hours ahead. Cover and refrigerate.
Preheat the oven to 350°F Bake the stuffing covered for about 1 hour or until heated through. Uncover and bake until the stuffing begins to brown on top, about 20 minutes.