I'm asking for help in the help section? Since when was that the wrong section? I've seen people ask about how to make other add ons here.
But that's weird. I just unzipped it again, and there's several .wav files in it, which look like MP3s. And I can open them and listen to them, too! So, what would I need to do to get the sound effects I want into the game? Change them to .wav's, and drag the .wav to the add ons folder? That sounds too simple. I see some other files in the Phone Sound folder, some text files and a server.cs. What are those for? Are they necessary?