If Last.fm had the rights to let you play that track, you could play it using the big "Play" button in the top right corner. Here's a song that is playable: http://www.last.fm/music/Mastodon/_/Iron+Tusk

But it's up to the rights-holder to decide whether to license the music to Last.fm. It looks like this band has only a few playable tracks: http://www.last.fm/music/Mastodon/+charts?rangetype=week&...