“Svelte and Sapper in Action” by Mark Volkmann is a good book.
There are also 10$ courses on Udemy:
- https://www.udemy.com/course/sveltejs-the-complete-guide/
- https://www.udemy.com/course/svelte-tutorial-and-projects-course/ (sapper is not included here)
- Good introduction to Sapper course by Net Ninja https://www.youtube.com/watch?v=-1hj5O-tQXo&list=PL4cUxeGkcC9gdr4Qhx83gBBcID-KMe-PQ&index=1