A while ago I received a video cassette of the June 1990 Screening Cassette of Ewoks: Battle For Endor used to promote its release on video.
The tape came with a promotional featurette that had a trailer from the film.
You can download the trailer in real video, but you'll need Real Player 5.0, which you can download for free at www.real.com.

Click here to download the trailer.