Title: New Discoveries at Jamestown
Author: John L. Cotter and J. Paul Hudson
The Gutenburg edition of this particular essay far outperforms the Librivox version by attacking the one weakness of audio books. The lack of images. Sure, my iPod can store images and I could even scroll through them as I listened to the book. But it's hard to look at them while driving. And without some sort of trigger to make the image show in the right section of text, it's harder to make sure you're looking at the right photo at the right time.
On the flip side of this, the audio version is a great idea if you're going to visit Jamestown, Virginia any time soon. While driving down (or up depending on where you are) you can get a very quick glimpse of what life was like in the early 17th century. Granted, this was written in the 1950s, but you can still get a basic idea. Discoveries have been made since and I'm sure more will be made years down the road. But in the meantime, you'll get a good overview of what you're going to see.
So check it out for a decent, free, and only slightly dated essay about Jamestown and the artifacts found there.