Model to test accuracy of 10-20 different forecasting methods given historical data

Hi,

What I would like to do is given a couple years worth of historical sales data, forecast future sales for the next month or so. This would be done in Excel or Access.

The problem is I am not sure which method to use (same week last year, rolling average, etc). Is there a module or add-in out there to test 10-20 or so commonly used forecasting methods and tell me which one is most accurate? I have a budget of about $200 for this.

Thanks!