I came across this blog about how to convey to those that you are giving presentations to data via charts and it’s a great source of information. Check out the Extreme Presentation by Andrew Abela where he gives you a visual sense of how to use charts. A great intro for using charts in Keynote, Numbers, and Pages in iWork.
For those that want to get more detailed in their analysis of data, you can visit processtrends.com and take a look at how Excel by Microsoft , R Project, and Google tools with Excel can help display your data visually on Google Maps. These latter site are not for the simple charts but are rather extensive and sometime complicated.
If you follow Guy Kawasaki’s PowerPoint (and Keynote) presentation guidelines called 10-20-30 you’ll maybe find the more detailed info beyond the needs of an entrepreneur, but they are here for your information.