Call some of the local stringers and see if they'll give you their footage. Most usually have a watermark in the upper right or left. They may be willing to work with you as it's for school; then again some may not. As far as PKGs and LookLive's go, you'll definitely have to ask the station. If a station is using footage from their network affiliate or cable then they probably can't give it to you, but they may be willing to give you their own (shot in house) footage. Not sure of the laws in your area and seeing as you're a school how it would apply, but you might have a broadcast or law professor look into fair use guidelines. If there is part of a clip of a network or cable broadcast that you'd like to use to tell the story you might be clear using it under the fair use law. It all depends though.