For additional resources, there are a lot of websites, blogs, and forums that you can visit to improve your game development skills.
For any questions regarding Cocos2d-x, its official website (http://www.cocos2d-x.org/) has a Learn section where you can access the Wiki, API References, and Documentation tabs.
It also has a Showcase section where the games created with Cocos2d-x are highlighted. So, when you create your next awesome game, you can showcase it there for promotional purposes.
Cocos2d-x has a very strong community. You can access it using the Community tab. The Forums are the strongest resource. You can post your query by creating a topic, and in most cases, there will be someone from the community ...