Currently Being ModeratedJan 29, 2013 9:09 PM (in response to E_Marie)
You have sent 49,000,000 bytes of data, and received 211,000,000 bytes of data using your cellular network during the "current period" also shown in Settings > General > Usage
FaceTime does take up data. The amount for each FaceTime call is shown in the Phone app under "Recents". Whether that data counts as cellular data depends on whether you're using cellular data or WiFi for FaceTime.
Currently Being ModeratedJan 30, 2013 9:43 AM (in response to E_Marie)
Many carriers will have their own app that you can download to your phone. It will have all of your account info and talk/text/data palns and usage during your current billing cycle.
Check the app store for your carrier.