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.

Good idea if you have a Spotify account.  Once you move up to lossless a streamer is recommended.

I am missing something here.  Why can’t he connect the computer to the DAC and use iTunes or Windows Media Player or whatever he has to play the files?  I haven’t played files from a computer for a couple of years but that used to be the drill...

You don't need an additional player or hardware. You need a program or software like itunes, jriver, audionirvana, foobar2000 and so on. See what mahler123 said.

So I can load the files on a tablet etc and USB them to the DAC.
I want to stay very far away from the Apple universe. And at this point not interested in streaming. I have been running thumb drives to my receiver in my cars for many years.

mahler123
Of course he can. That is NOT what he asked to do.
bsme85
You need a stinking computer for that. Pass.

rick
I too have gobs of thumb drives for auto. I play them exclusively during travel. The first thing that goes in a rental.
Don’t bother loading them on anything. Just plug them into the aforementioned devices and play. If you have a Samsung TV try that. Most streamers PLAY them. No mention of streaming. Ignore the man behind the curtain.
When you realize how much better lossless sounds you will be glad that you can play them too.
The Roku route is mp3 only and a cheap splitter will get it to the Sprout.
https://www.ebay.com/itm/254950382457?hash=item3b5c3a1b79:g:3YYAAOSwOQhgf98r
I’ve spent years upgrading my library from mp3 after I moved from computer to streamer players.

I dunno...  Plex?  foobar2000???  There are actually just a few programs that seem to do the job - just manage the connection from hard drive (local?  network?)  to your preamp/receiver/whatever.  Heck, a number of receivers, etc. can be set up to connect to & play stuff on network drives - if you can present your source on the hard drive to whatever you use it's become surprisingly easy to play 'em.

Fuzztone

  The OP asked asked “How do I get my mp3 s from my Hard Drive to my speakers?”  Since no other information was supplied in this pithy post, I assumed that he has his files stored on a hard drive.  Most people use the term hard drive to either denote storage on a computer or an external hard drive.  I therefore asked why can’t he just use whatever media player is on his computer.  
OP

You don’t need an Apple device.  A Windows Or Linux Computer will do the job.  You may have to add an extra driver for Windows as that is common with many DACs.

  Streamers are just specialized computers.  They are made to resemble traditional audio components.  They are computers that are optimized find files stored on a hard drive somewhere or else pull the files from the Internet (Streaming Services, such as Spotify). They then send the files to a DAC, or else they include a DAC and then send them to amplifier.  Since they are specialized computers, their functions can also be performed by a general purpose Personal Computer.

  Since you wish to avoid Apple, and you apparently want the convenience of using a tablet to control the files, you will need an Android Tablet that can control the Computer OS wirelessly.  Your idea of tethering a tablet by usb to the DAC is again one that I am struggling with.  It kills the advantage of using a tablet, namely being able to control the files without having to stand in proximity to the equipment.  And are you going to have a thumb drive sticking in one end of a tablet and the usb cable sticking out the other?  Tablets are also specialized computers, with stripped down storage and OS.
Unless you are one of the 14 people on the Planet that doesn’t own a Personal Computer, just use that for now.   Stick the thumb drives in the usb input, connect the usb out to the DAC, and use either the computers media player or a downloaded program to control the files, and Bob’s Your Uncle When you tire of doing that, and wish to own a dedicated streamer, take that plunge.
  And if you are only interested in playing mp3 files, don’t have so much angst about it.  They will sound lousy no matter which route you take

So I can get a tablet with good storage, stuff it with MP3s and put a Jriver or equivalent program and right now stream to the Sprout via Bluetooth as I do with Pandora. and then when I upgrade away from the Sprout, just make sure I have a Blue toothable device hooked to the Freya +.
Or am I totally wrong? 

Yep