How to Move Unzipped MP3 Files Into Your iPhone (Method #1)
Click here for Method #2
I wish I could say that moving MP3 files into your iPhone via iTunes was easy, but it's not. It happens that iTunes wasn't designed to be intuitive, thus the long sequence of steps necessary to make this work. So try method #1 first, then give method #2 a try if you don't succeed initially. This method uses the latest version of iTunes (V 11.0.1.12).
1. Connect your iPhone to your computer and let iTunes come up or start the software yourself. You should seen the following panel:

2. If you don’t see this panel, then Click “View” on the top menu and select, “Show Sidebar.”

3. Now make sure the “Music” button is selected in the top left hand corner.

4. Select the “Music” button if it isn’t.

5. Next, click the “File” menu on the top bar, then click “Playlist” This will create a new Playlist for you, which is folder that will house the audio files that you’ll drag into it shortly.

6. On the left side bar, you’ll see a location where you can name your new Playlist.

7. Give your new Playlist a name such as “Machado Book.”

8. With the “Machado Book” Playlist selected, drag the files, or a file folder or all the file folders to striped panel below the “Machado Book” Playlist to the right of the left sidebar. How do you do that? See Step 10.

9. From Windows Explorer (you know what that is, correct?) drag files or a folder of the ebook to this gray area.

10. Now, if the file numbers are not properly sequenced as they weren’t in Step 9, then click the “Name” selection just above the first file. Click it again if the files don’t start with the lowest number and increase downward as shown below.

11. Now look at the left sidebar on iTunes and click on your iPhone’s name.

12. You’ll see the following panel open up.

13. At the top of that panel, click Music (yes, you have audiobook sound files but iTunes recognizes these individual MP3 files as music files.

14. Below, under “Playlists” you’ll see the “Machado Book” playlist. If it’s not checked, then check it.

15. Click the “Machado Book” playlist as shown below.

16. Depending on how you have iTunes set up, the following dialogue box might open. Click “Apply.” This will automatically sync your new files with your iPhone. If the dialogue box above didn’t appear (this depends on how you have iTunes originally configured), then you need to sync your phone manually.

17. To manually “Sync” your iPhone, go to the bottom right hand side of the same page and click “Sync.”

18. iTunes should now Sync your newly added audio files with your iPhone. To see them, go to your iPhone and click the orange music button.

19. Next, click “Playlists” on the bottom left of your music panel and you should see the “Machado Book” Playlist show up in the queue.

20. You should see audio files in the panel.
