Earlier today I found a great service for those who play guitar, Youtab. This great service gives you the chords from youtube-videos. Among all the famous songs I found a great cover of Rihannas “Diamonds”.
Youtab gives you the chords to your Youtube-videos
Saarimner.com 
Hey, just letting you know that YouTab has relaunched with many cool features. Check it out at https://www.youtab.me/
All the best.