Where is it? Find the tutorial here.
What is it? A comprehensive look at how to create a contact book in Python with a GUI of your liking, using SQLite as a data store. The tutorial shows you how to use PyQt's Model-View architecture to manage contact data. At the end, you will be able to build any application you want that supports CRUD functionalities.
What you need to follow? Some previous knowledge of GUI programming with Python and PyQt will help but you should be fine even without it. The tutorial provides resources which further explain these areas to help you clearly understand them.