You'll need to venture into Code View for that. IDs and Links are not stored in a separate file - they are stored in your HTML page, but you can only really see that in Code View which shows you the code behind the look of your page.
Book View is ok for adding and modifying ids and links, but its not setup to delete them.
In Code View you will be looking for tags that contain id="...." for the IDs, and href="..." for the hyperlink references (links). If you delete any, remember that ids are also used for Table of Contents entries (and indexes if you have set one up).
You can use Find & Replace across All HTML files, and search for id=" and href="
The Insert ID and Insert Link buttons are just shortcuts to entering that text for you.