Im assuming you use windows.

Use the latest AMD Driver + AMD-APP-SDK-v2.8-Windows
https://bitcointalk.org/index.php?topic=150331.0 is the easiest way if you new to mining. If you experienced with cmd and stuff then go straight for cgminer alone.
How to point you miner to give-me-ltc and set up workers is explained on the give-me-ltc page.