I stumbled across this tonight, and thought it was interesting. It's the pre-launch promotional campaign video for Star Trek: The Next Generation, sent to networks 10 weeks before the first episode of TNG aired. It talked about how they were promoting the show nationally, and how local networks could promote the show too.
It also mentions a Cheerios sweepstakes to win a walk-on role on the show. It appears that sweepstakes was ultimately won by an elderly woman who declined her prize.