Here are some of my favorite resources to help you choose the perfect chart for your data.
hint: (click on the green text or images for links)
The Graphics Continuum shows several ways that data can be illustrated individually or combined to show relationships.
Financial Times Visual Vocabulary: Tableau Edition shows every chart represented in the Financial Times Visual Vocabulary. (Created in Tableau by VizWiz Andy Kriebel in collaboration with other Tableau masters.)
From Data to Viz is a fascinating decision tree that leads you to the most appropriate graph for your data and lists common caveats you should avoid. This resource also offers the code to build the appropriate graph in R, Python, and D3.js.