I have a 1999 ford contour after I ran out of gas, I added 2 gal of gas and it won't start"

It is possible that when you ran out of gas air got into the fuel lines. What you will need to do is turn the key into the run position(not into the start position) and leave it for 30 - 60 seconds. This should engage the fuel pump and allow it to pressurize the system. After letting it sit try and start the engine letting it crank for 5 - 10 seconds at a time. You may need to repeat the process a few times. It is also possible that when you ran out of fuel you damaged the fuel pump and it may need replacing. When you put the key into run see if you can hear the fuel pump running. I hope this helps you out.