When creating a new course, you can choose if you want content copied from any existing course. There is a model course shipped with WeBWorK, but it is not in the courses directory, so to use it you need to either copy it there or create the symbolic link that Andras describes. Either of these requires access to the server.
You have the option of creating a course to use as a model for future courses (or even multiple model courses). Then when you create a new course you can select whichever one you want as a base. Note that when you copy content from an old course, it only copies files, so assignments are not copied. The best way to handle this is to export your assignments in the old course. Then they will be available to import into the new course.