Carnegie Mellon provides several good campus maps.
My office is 5419 in the Hillman Center for Future Technologies ("Hillman"), which is part of the Gates Hillman Complex (GHC). If you need to ask someone for directions, most people will know where Gates is; Hillman is less well-known. The asterisk (*) on the map below shows where my office is located in GHC. This map is also available in pdf.
Pittsburgh is a city of hills, so my building has an unusual floor numbering system. You will probably enter the building on the 4th or 5th floor. My office is on the 5th floor.
If you prefer an interactive map, a Google Maps satellite image is provided below. The blue markers show the locations of my office, the bus stop, and the parking garage (hidden, on the right). Click here to see a larger map. If you zoom in, it looks like my office shifts from Hillman to Gates, so beware.
If you are using a navigation system to find CMU, our address is 5000 Forbes Avenue, Pittsburgh, PA 15213. That will place you near "the cut", an open grass quadrangle at the center of the campus. The parking garage is a three-floor yellow brick building just a little farther up the street.
Carnegie Mellon has a reasonably good visitors page that has information about finding CMU, hotels, parking, campus maps, etc. It is a good place to start.
If you need a hotel, CMU's visitors page lists many, including many that are not near the campus. CMU is in the Oakland neighborhood. The Shadyside neighborhood is nearby. Everything else is too far away to be practical unless you have a car.