The MacOS X port of Quake requires the data files of the retail or shareware version of Quake.
Install the Classic MacOS or PC version. Only the "id1" folder is required.
Delete the "glquake" folder, which is located inside the "id1" folder.
Copy the MacOS X Quake application(s) to your Applications folder.
Optional: Copy the "qw" folder into the "Quake" folder, if you want to offer a QuakeWorld server (the "Quake folder" is the folder that holds the "id1" folder).
Note: You will be asked to locate the "id1" folder which comes with the shareware or retail version of Quake, if you startup Quake for the first time and have not placed the Quake application(s) inside your Quake folder (the "Quake folder" is the folder that holds the "id1" folder).