Here are a few samples to help you start your thinking.
[youtube http://www.youtube.com/watch?v=t3lSSp-3068&rel=0&hl=en_US&feature=player_embedded&version=3]
With iMovie, you do not have quite as much freedom with your typography, but something similar is still doable.
[youtube http://www.youtube.com/watch?v=VkCFeNeqyHk&fs=1&hl=en_US&rel=0]
This is a great example of using captions and images to illustrate your poem.
[youtube http://www.youtube.com/watch?v=LWmU0hze4jE&fs=1&hl=en_US&rel=0]
Though this isn’t technically a poem, it’s a great example of how images and music complement the text.
A final resources is the Poetry Foundation.
Here are two more very cool videos.
[youtube http://www.youtube.com/watch?v=rCuIFBCvSPM&fs=1&hl=en_US&rel=0]
Great use of imagery.
[youtube http://www.youtube.com/watch?v=t3WBH5Mc6tw&fs=1&hl=en_US&rel=0]
Excellent use of animation.