How to back up data stored on time capsule to an external drive

Thanks for your reply, I have the time capsule set up and running fine. I can transfer data to the Data folder within time capsule, my question though is how to back the data up that is stored to an external hard drive plugged into my computer (in System Preferences, I select the 3TB to be the time machine back up but it doesn't back up the drive on the time capsule.)

Thanks for the archive info, but is there a way to have it back up through time machine? Time Machine is awesome and I like how it backs up all the time as you make changes. Is there a way to back up the data using time machine? I could put the external drive into the port on the time capsule, would that back up the time capsule as well as my Macbook?

Thanks for your help, a bit dissappointing as I called Apple and asked them specifically if I would be able to do this with Time Capsule and was told that I could (that was the reason I went with this setup!). I will work with the archiving function to save Itunes folder stored on Time Capsule and set up Automator to do this periodically. Thanks!