Python has been integrated into Cinema 4D since the release of R12. And surprisingly it is still hard to find good learning resources for beginners. Here are some of them I found myself to be the most useful.
1. Cinema 4D Python SDK
First there is the Python SDK by Maxon. It is a good reference and relatively well documented (although you sometimes have to switch to the C++ SDK). As a starting point for beginners you might feel overwhelmed by the pure amount of content and it is surely better to start with some tutorials to guide you through.
2. Cinema 4D Plugin Development Support Forum
If you build a plugin and get stuck at some point, you should not hesitate to ask the guys at Maxon’s plugin development forum. Even on „noobish“ questions they are kind and helpful. As I learned the basics of plugin development they helped me out multiple times.
3. Tutorials by Pim Grooff
Pim Grooff is a Dutch IT consultant who has a remarkable blog with lots of good python stuff. His tutorials and examples range from a beginner to more advanced level. If you search the web to find useful resources you will definitely stumble upon his site.
4. Tutorials by Michael Auerswald
Michael Auerswald is working as a technical director in Berlin and has some really good tutorials especially for beginners. When it comes to understanding the basic structure of plugins you should really check his tutorials out. He even offers a course on python scripting at fxphd.
5. Cinema 4D Advanced Production Techniques
This is a tutorial series which where recorded and screen captured at seminars in Copenhagen and Berlin. There are some really good talks covering python issues. But as the title includes they are mainly aimed at the more advanced users.
(6.) Type name and ID list
If you’re plugin generates basic Cinema 4D objects you will often find yourself looking for type names and object IDs. Glen Faught put together a helpful list of most of them so you don’t have to find them out every single time.