For now you can stay at the simple end of the spectrum and use a list. You can make a list with the function, which, appropriately enough, returns a list of its arguments.

Note that you can create a property list with the same function as you use to create other lists; it’s the contents that make it a plist.

Given all that, you can easily enough write a function make-cd that will take the four fields as arguments and return a plist representing that CD.