Sounds like you didn't check the Sticky as suggested. How to transfer music to my iPod (& iTunes) for mac users. Double-check the songs aren't already in the iTunes Library. They might not have proper id3 tags which means they'll probably be at the bottom of the library list. Another "Quick" way to check is go to iTunes Edit menu -> View options & tick option to show Date Added. Then find that column & click on the top of the column. This will arrange the songs with the most recent at the very top of the library list. This way you'll know for sure whether your songs have been added. Perhaps the id3 tag is different to what you expected or doesn't have one so is normally arranged by file-title instead of by artist (which as I suggested normally puts them at the bottom of the list.)

I would also recommend getting Audion (free) as to check the songs play properly just in case there's problems with any of the files. Audion "can" play mp3pro format. If you have any in mp3pro format, you can use Audion to convert to AIFF. Then import to iTunes & convert to apple lossless or mp3 or m4a.

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