I think I found the answer on my own. Apparently I have to work through the list of 40 chapters in the book window and replace each chapter with the newly copied chapter under the new folder structure.
If anyone reviewing this can confirm or correct me, please do so. I'd rather not leave behind incorrect information like this on the forum if I'm wrong.
Your concern for the future readers of your thread is reassuring.
The Book file contains pointers to the locations of those files on your filesystem. I'd recreate the book - I'd move my chapter files to the new location, then add them to a new Book file.
You're going to have similar problems with Links, by the way. All of the links are still pointing to the original locations if you just did a copy of the folder and changed the name. ID uses absolute paths for links unless it cannot find that path, then it looks in the current folder where the .indd file is stored and subfolders. Maybe that isn't a problem (that is you don't dont want multiple copies of images floating around with the same names so both files really should link to the same places), but if you expect two completley self-contained units you should use the Package command on each file to make the duplicate of the file, the links, and to relink to the duplicates.
I think the best way to duplicate all the files for a project is to use the Package function under either the book panel, if you are working on a book, or the File menu for individual files. InDesign will then move the files and relink them properly for you so you don't have to do it yourself. This avoids all the messiness that's discussed in this thread.
Thank everyone for the feedback. I wasn't aware of the package feature you mentioned so I'll investigate that possible solution.
I successfully updated the book file to point to all of the copies... it just took a while with 40 chapters.
I suspected there would be an issue with the image links. I'd like to find a solution to that as well. Since I'm the newest person on the team but solely responsible for his particular document, it is up to me to fix things without rocking the boat too much. (politics)
After investigating a few of the links, I see that some of the hundreds of images are pointing to indivisual computers belonging to people no longer employed by the company. I'm finding links pointing to user folders on distant C: drives.
I don't mind independent copies of the entire project with all the images in folders below the ID files. Wish those links were relative paths instead of the full path but it is what it is... I am more concerned with the missing images and the fact that ID now has to use whatever temp file it is using to display the image of the missing file.
Sounds like I've got a busy week ahead of me... but I'm done for now... got my 40 hours in and I'm not authorized any overtime no matter how much I'd like to clean this up as quickly as possible. :-)
If you have missing links you have a problem. You can't get quality output from the preview.