I am trying to analyze demographic information across 10 main zip codes that surround my area of interest. How would I be able to compile the information I have to give me the demographics of the combined areas?
You may need to provide more information regarding the format of your data. Is it in .csv files or in shapefiles (i.e., shp)? Shapefiles may require specialized software in order to modify. No matter what your file format you will need to define variables of interest for the zip codes and make sure that you produce a categorical variable containing the zip code value.
Also, some more information regarding what you want to analyze will be helpful. This may determine how you organize your input data file for analysis. The statistical package will also matter.
Wooldridge (2009) has a good chapter (ch. 19) for preparing for an econometric analysis project that you may want to review.