How do I import mp3 files into iTunes?

Where are you selecting "import file" because the way to add an MP3 to your iTunes Library is either:

• File/Add file to Library
• CTRL O

and then navigate to the folder with the file in it.

Providing the MP3 has the tags filled in that supply the song title, artist name and album name (among other things) you can then search your library by theose items or simply browse for them. Have you searched your Library for the song title?

And therein lies a cruicial difference between importing and adding.

• When you import music, you "bring it in" from somewhere and put it somewhere else. For example, you import the files from your external hard drive into your computer. (They are not yet in your iTunes Library though.)
• When you add music to your iTunes Library, you are doing just that - adding something that is already in place, to your Library. For example, if you already have MP3 files on your computer, you then add them to your iTunes Library.
• So in your case, you need to import the files from the external drive to your computer (drag-and-drop, or copy-and-paste) and then add the files to your iTunes Library, using File/Add file to Library or CTRL O.

By the way, if you simply use "Add File to Library" and navigate to the external hard drive, you create a link, which will be broken once the external hard drive is disconnected. Then iTunes will no longer be able to play the song, because it cannot find the song. That song listing in your iTunes Library have an exclamation mark next to it.