Do you need some historical stock data to play with? This is the easiest way to get some basic free data. (Keep in mind this data is free, not error free, but decent for simple graphing and testing formulas. I would purchase data from a reputable source to trade from.)
1. Go to the Yahoo Finance website
2. Enter a stock symbol and hit GO
3. Click Historical Prices on the left side of the screen
4. At the bottom of the screen you will see

5. Save the spreadsheet to your computer, this saves it as a *.CSV file
6. Open the file with excel. You can copy and paste the data into another workbook, or save the file as an *.xls file.