Basically:
Put all the sounds as .wav format in a new folder in Add-Ons. ("Sound_MyNewSounds")
Create a file "description.txt" in the folder, and write something like this, then save it: (You must keep the Title: and Author: parts)
Title: Sound Pack - My New Sounds
Author: Lord Templar
Some new sounds for the game.
Create a new text file, and rename it "server.cs". Say 'yes' to any dialogs about changing the file extension. Open this file in a plain text editor. (e.g. Notepad, not Word on a Windows computer)
For the first sound, add this code, changing the bold parts:
datablock AudioProfile(First_Sound)
{
filename = "./NameOfSoundFile.wav";
description = AudioClosest3d;
preload = false;
};
For each one after this, add this, changing the bold parts:
datablock AudioProfile(Another_Sound : First_Sound)
{
filename = "./NameOfOtherSoundFile.wav";
};
Save this, and put the files (not including the folder!) into a .zip.
Alternately, if you really get stuck, send me the files by hosting them on some website and I'll do it for you.