Just found out that you do not need any special software to join multiple MP3 files together. I’m sure that this is an old trick, but wanted to save it here as so I will be less likely to forget it.
In Windows:
copy /b File1.mp3 + File2.mp3 + FileX.mp3 NewFile.mp3
In Linux:
cat File1.mp3 File2.mp3 > NewFile.mp3
For both methods, you can also use wildcards instead of explicitly naming each file.