Hi Mel - I have found this video tutorial on how to add a BOOK
Create a CHAPTER called session plans. Then add your Google doc session plans as a link within the description box.
I can see that you have managed to create a book in your tutor file - you now need to go in and create your chapter within your book.
Have a go - I will try to add a step by step guide to the Moodle Support Page
Nic