How do I get my audiobooks to show up under the Audiobook section? I have audiobooks copied to my iPhone that I didn't buy on iTunes. How can I get them to show up in the Audiobooks section?

It's annoying having them mixed with music, because I usually use shuffle.
It's easy to tell iTunes that an audio file is an Audiobook. That will automatically put it in the right section, and not play it when shuffling.

Select the tracks you want to mark as audiobooks and go to File-> Get Info-> Options. Set Media Kind: to Audiobook.