The following post seems particularly useful for people that are relatively new in the field of data visualization and might consider developing their own graphs or interactive applications. Should you program or not? What tools should currently exist? What visualization frameworks are available?
The good people of the Swiss website called datavisualisation present "A Carefully Selected List of Recommended Tools" [datavisualization.ch], containing a set of hand-picked software libraries, applications and services that they use regularly for their own infovis work. The current collection contains three different categories: libraries for plotting data on maps, frameworks for creating charts, graphs and diagrams and tools to simplify the handling of data, and will be updated regularly. A filter in the right top corner allows to exclude those tools that require programming expertise.
More detailed information is available here.