I have a fairly basic and flexible version (See Link) that I thought might be a helpful place to start if you are thinking about monetizing a content based (i.e. "eyeball" or advertising based) business.
**Hint - don't start unless it looks REALLY good because no one ever seems to meet the pro formas (at least not in the short run).
For more in depth help (or if you are a Spreadsheet Jockey in training) there are any number of books, etc. available.