Download and install Audacity.
Import the first two tracks of the audiobook into audacity by going to "File" and then selecting "Import".
Select the second track, and then go to "Edit" and choose the "Find Zero Crossings" option.
Go to "Edit" and then select "Cut".
Select the first audiobook track and then move your cursor to the end of the audio track.
Go to the "Edit" menu and then select "Paste" to copy the second track onto the end of the first.
Import the subsequent tracks of the audiobook into Audacity and then continue pasting them onto the end of the initial track until you have done this with them all.
Select "File" and then choose "Save as" to save your audiobook as one complete file.
Download and install Merge MP3.
Open Merge MP3 and then import all of the separate audiobook tracks into Merge MP3 by drag and dropping them onto the program's window.
Organize the individual files into their sequential order by clicking the file name banner on the list of tracks.
Select the "File" tab and then choose the "Merge" option. This will combine the individual audio files into one continuous audiobook.
Download and install MediaJoin.
Open MediaJoin.
Import the audio tracks of the audiobook into MediaJoin by dragging them onto the program's window.
Select "Audio" under "Media Type" on the MediaJoin program window.
Click the "Join" button, which will bring up a window prompting you to name the consolidated audiobook. Name the file and then click "Join" again to combine the files.