Q: When loading audio books onto my iPod, they do not appear in the “Audiobooks” folder on my iPod or even in iTunes. Nor can I add any new categories or folders other then the 5 or 6 that came with the iPod (ie, Music, Movies, TV Shows, Audiobooks etc).
– Susan

A: The default categories that appear in the source list in iTunes are somewhat fixed. These can be hidden or displayed via a series of checkboxes in iTunes’ General Preferences, but you cannot further customize them or add your own.
The only option for additional organization is to create folders and playlists within the iTunes library, which appear further down in the source list.
Folders are only shown within iTunes and on the iPod classic and iPod nano—other models of iPod omit the folder structure and display only the playlists.
Content is organized into these various main categories based on tags within the content files themselves. Most audio content is imported as “Music” by default, and most video content as “Movies.” Video content can be re-categorized as “TV Show” or “Music Video” from within the individual track properties, but no such built-in option exists for audio files.
Normally, audiobooks downloaded from the iTunes Store or Audible.com come into the Audiobooks category automatically. Other files that you import yourself will default to being listed as “Music” even if they happen to be audiobooks initially.
There is a workaround to this, however, if you want your own audiobooks to be listed in the “Audiobooks” category: Simply encode the file as an AAC file when you rip it from CD, or convert an existing MP3 to AAC. Then, rename the resulting file from “.M4A” to “.M4B” before importing it into iTunes. This will place it in the “Audiobooks” category during import.
If you have already imported the file as an M4A, you will need to remove it from the iTunes library (ensuring that you select “Keep Files” when prompted as to whether or not you wish to delete the actual file) then rename it to M4B and reimport it.
MP3 files that you’ve already ripped will have to be converted to AAC (.M4A) before you can do this with them.