Script book or guide

Apart from books and resources the main thing to start with in my opinion would be the folllowing

• Learn basic programming and JS skills.
• Based on your know how of using the apps, familiarize yourself with the DOM API for JS. This will help you put together an idea as to how an operation done on the UI would be mapped to the API's and you will be able to string it together with the help of logic implemented via the programming skills you learnt in the first step
• Look up sample scripts shipped with the apps and understand how they work.
• Now try writing your own scripts and if you get stuck, head back to these forums with your queries.

-Manan

there aren't many books about scripting, about the only author out there is Davide, check out his work here

https://www.davidebarranca.com/

info is out there though, check tutorials on Youtube, then ask questions here is you get stuck.