Nathan, the guy behind the code at the FlowingData blog, offers up a good how-to set for producing interactive area graph.
How to Make an Interactive Area Graph with Flare
You've seen the NameExplorer from the Baby Name Wizard by Martin Wattenberg. It's an interactive area chart that lets you explore the popularity of names over time. Search by clicking on names or typing in a name in the prompt. It's simple. It's sexy. Everybody loves it.
This is a step-by-step guide on how to make a similar visualization in Actionscript/Flash with your own data and how to customize the design for whatever you need. We're after last week's graphic on consumer spending:
Audience
This tutorial is for people with at least a little bit of programming experience. I'll try to make it as straightforward as possible, but the concepts might be a little hard to grasp if you've never written a line of code. Just a heads up. Of course it never hurts to try.
If you don't care about customization or integration into an application and don't mind putting your data in the public domain, you could also just dump your data into Many Eyes, and use the Stack Graph.
Get Adobe Flex Builder
Like I said, this is all in Actionscript, so before we start anything, I strongly recommend you get Adobe Flex Builder if you don't already have it. You can buy it, get a trial version from the Adobe site, or if you're in education, you can get it for free.
There are ways to compile Actionscript without Flex Builder, but they are more complicated. [read more here]