How do I get my mp3s from my hard drive to my speakers?

Paul doesn't believe in that.  You need a player.  A Roku, Sony Blu Ray, NAD CD player, most any streamer except Sonore and Metrum, etc.
With the Roku and a cheap monitor you can see what you're playing.
Can't play squat without a player.  Scott could have easily built one in the Sprout but no....

With my system, I was able to add my songs from my hard drive to my Spotify account. My Marantz ND8006 CDP has a Wifi streamer with a decent DAC. So I stream from my iPhone to the Marantz. Works for me and sounds excellent, Hope this helps.