Where can you find the sheet music for Super Mario bros main theme?
ninsheetmusic.net. Edit: You can also try "http://www.free-scores.com/download-sheet-music.php?pdf=9240"
The music for Super Mario was written by a composer named Koji Kondo. Nintendo has not released the official sheet music for Super Mario. However there are many fan made versions available on the internet. You can hear many remixes of the song over many Nintendo video games such as the super Smash Brother series of games.