Dig around in your EverQuest II / music / zones / _exp09 directory - I don't recall exactly what music was in HE, maybe mx_drinals_castle_themev2.mp3 ? Anyhow - the directory structure is such that the _EXPXX coincides with the expansion.... for the most part.
I rather forgot about the vast collection of .mp3 files stored locally. I Thank You for reminder; heh, I need to go back to Harrow's End to verify, but pretty sure I found the appropriate files.