Online DCF model
Here is a simplifyed online DCF model, insert appropriate figures in cells and press calculate.
This model allows you to calculate the value of the company really fast but with a poor accuracy .
To construct a full scale DCF model for the appropriate valuation you need much more inputs and totally different forecasting mechanics.
This model may help you to understand the mechaincs of DCF. 
Instructions
Year 0 is the previous year from now. If now is 2011, then "Year 0" is 2010, "Year 1" is 2009 and "year 3" is 2008. So if it is 2011 please insert values for 2008, 2009 and 2010
 Please insert all the data in the cells below. A good source of financial information is Yahoo. You should insert stock's ticker in the box, choose your company and click on Income statement, Balance sheet and Cash flow in the left menu bar.
 After you inserted all the data in the cells press the button "Calculate DCF model". Below you will see the forecast of P&L statement, Balance sheet, Cash flows statement, WACC and DCF model with an estimated fair value for the stock.
 Note that the major share of company's value comes from the post forecast period (terminal value). When creating a model, try to focus on the last cash flow in the forecasting period ("Year 2") because it defines terminal value.
 Use debt (short term and long term) as a balancing row when the company shows negative cash at the end of the period.
 After you created a model for the first time you can make changes in inputs and calculate the value again. Thus you can analyse the sensitivity of your model to changes in wacc, growth rates, profit tax rate, etc.
