I located an online tool that will allow you to extract the audio from any video file. You can provide the link to an online video, including YouTube, and the utility will create an mp3 of the audio. You can also upload your own video file. I’m not sure what the size limit is but when I tried to create an mp3 from a video file larger than 8 minutes or 4 MB the tool stopped working. Once the mp3 has been created, you can right click on the link, Select Save Link As and save to your PC.
I created the following mp3’s using this utility. Feel free to download them.