I found these after exploring my Red Alert 2 and Yuri's Revenge modding files. Apparently, by modifying the theme.ini (or thememd.ini for Yuri's Revenge), you can add more music in the game playlist.
Below are the music files in WAV format. This WAV format is the only format RA2/YR can recognize.
Maybe I'll post an MP3 version soon.
DOWNLOAD 'Set the World on Fire'
DOWNLOAD 'Fight it Back'
DOWNLOAD 'Till the End'
DOWNLOAD 'Campione 2000'