I need to add to drip lines to an exsisting sprinkler head. I can not replace the head It still needs to operate. How do I do this?
So you want to do something like water the lawn with a sprinkler AND water something like a flower-bed with drip irrigation on the same circuit? That is generally considered a bad idea for two reasons: Usually drip irrigation needs to be scheduled different than lawn sprinklers (such as needing to run the drip system twice as often as the lawn), and its difficult (though not immpossible) to match precipitation rates (you usually wind-up either watering the lawn too much or the flower-bed too little). Sprinkler flow rates are measured in Gallons Per MINUTE, while drip systems are measured in Gallons Per Hour.
But if you MUST combine the two, you basically will need to Tee into the existing line running to the sprinkler head and run a line to where you need the drip irrigation. Then to make the below ground to above ground transistion, you can use something like this (
http://www.sprinklerwarehouse.com/1800-RETRO-Retrofit-Kit-p/1800-retro.htm ) to get the pressure regulation and filtering the drip system needs.