Clean the rabbit and cut into large pieces. In a large skillet over medium heat, heat some olive oil. Add the garlic, then after a minute, add the rabbit and rosemary. Season with salt and pepper. Cook for 10-15 minutes, or until the meat is cooked through. Remove from the pan and allow to cool slightly. De-bone the rabbit and chop coarsely by hand or in a food processor. Set aside.
Add the onion, celery, carrot, and parsley to the skillet with the rabbit drippings and a drizzle more of olive oil. Cook over medium heat until golden brown. Add back the ground rabbit and the wine. Cook for about 5 minutes, and then add a cup of broth or water. At this point, if you prefer a red sauce, add a cup of tomato puree in lieu of the other liquid. Cover and cook for 20-30 minutes, adding a bit more liquid if it seems dry while cooking.
Meanwhile, bring a large pot of salted water to a boil. Cook the pasta until al dente. Drain and add to the skillet with the rabbit mixture. Cook together for a minute. Serve immediately with a sprinkle of Parmigiano.
If you have time to make your own rabbit stock, you can simmer the rabbit bones in a quart of water with onion, carrots, and celery for an hour, and then strain.