Just right click all tracks in your book, they are probably in the Itunes music folder, if you don't already know holding down shift or control will highlight more than one thing at a time.
from the menu that pops up when you right click, choose Get Info, then Iptions, then Media Kind and then choose Audiobook and all the files will move to the audiobook folder and Itunes will know they are a book, enjoy.
I used to use a program called Media Join to make the cd's I got from the library into one file for each book, some of those cd's have 90+ tracks and it's easy to get a track out of order or lost. If you have a book with tracks labeled 1,2,3 on all discs, I'd make an audiobook folder for each book, but if they are labeled 1-1,1-2, etc. then you can put them all in one folder and nothing will get confused. Karen