JupyterLab is relatively new amazing software. So you will not find many good books that cover simple usage, creating extensions or user manuals. Also JupyterLab is constantly improving and adding new features. So a printed book would be obsolete when it is printed.
The best reference to use for JupyterLab is:
This is the manual created by the developers, maintainers and community. This documentation contains everything. So:
User guide. Very complete and perfect for everyone who is new starting with JupyterLab and IPython.
Extension Developer Guide: Must read documentation if you are creating extensions for JupyterLab.
JupyterLab Developer Guide: The guide if you want to contribute to the next verion of JupyterLab or want to know how to submit your bugfix. This guide also contains the full JupyterLab API Reference.
This guide is always up to date and contains a good changelog for major and minor updates on JupyterLab.
The Jupyter project has great documentation for IPython and every thinkable aspects of the Jupyter suite. Check:
For a comprehensive list of links to each of the documentation repositories of Jupyter subproject.
IPython provides a rich toolkit to help you make the most of using Python interactively.
JupyterLab with the Python kernel has full support of all options available in IPython. So to get the max out of JupyterLab when working with Python you should use the up-to-date version of the IPython documentation.
For the up-to-date IPython documentation.
Binder allows you to create custom computing environments that can be shared and used by many remote users. Use it to share an executable version of your notebook.
Full docs on: https://mybinder.readthedocs.io/en/latest/index.html