The CS department is on the right, in the Levine Science Research Center (LSRC). About the time you see the Duke Tower, the LSRC will be between you and the tower. It's a few hundred yards down from Erwin, shortly before Research Drive ends at Science Drive. There's a sign out front. The CS department is in the wing closest to Research Drive.
To get to the visitors parking lot, turn right off of Research Drive just before the LSRC, into an alley between the LSRC and another building called North. Drive the length of the LSRC to a gate. There's a keypad and directions to dial the CS department secretary to buzz you in (you may have to dial the main desk, 660-6500).
Find a parking spot marked visitor, then walk back the length of the LSRC, inside or out. My office (D304) is on the third floor, on the Tower side, way at the end of the building, closest to Research Drive.
If you have any problems, call me at (919) 660-6551, or the department main desk at (919) 660-6500.