Simply add the Spotify Play Button to your google site and strike up the music. You can feature any song, album or playlist. Your google site visitors will only have to hit the play button. It's completely free, legal and awesome. Check it out on spotify So here is how you would embed it on your google site ....
Insert > More Gadgets > Featured > Embed Gadget > Paste in the code below:
<iframe src="https://embed.spotify.com/?uri=spotify:track:4bz7uB4edifWKJXSDxwHcs" width="300" height="380" frameborder="0" allowtransparency="true"></iframe>
Change the height of the gadget in both height fields to 380 > Change the width to 300 and make sure pixels is picked from the drop down menu > Untick display the title on your gadget field
The just save!Let me know how you get on.
Here is the working result!