You can find the installer here:
http://www.amrein.com/apps/page.asp?Q=5749
And it is FREE!
If you are the administrator, you can download and install it by yourself. Otherwise, ask your web administrator instead :)
By the way, I have tried to use this feature.
If the feature has been installed in Sharepoint server, the feature will be in the web part list. So you just have to add the web part :)
The chart can extract data from the existing list in your site, or you add a new list.
Configure the setting in Miscellanous part when you edit the web part. If you configure it correctly, the chart will be shown at the web part zone as example below:
Now you can have graphic on your site!
:)
