The Node Reference URL Widget module adds a new widget to the Node Reference field type. It auto-populates a node reference field with a value from the URL, and does not allow this value to be changed once set. It can automatically provide a link on the referencing node types, that will contain the proper URL to prepopulate the field.
Book Delete adds the ability to delete entire books to the book administration page (admin/content/book).
It uses a batch operation to allow deletion of large books.