Not all of them are Official, however I put the character names for what Album they are on. Not all of the songs are in English, Japanese, or widely known, so i will leave links to translations here in the description to most songs if any of you want to read along~
[[[Will Add More When I Get The Chance]]]

Prussia's - http://lyricstranslate.com/en/monsta-monster.html
Germania's - http://herzeleid.com/en/lyrics/reise_reise/reise_reise
Rome's - http://hetalia.kitawiki.net/index.php?title=Roma_Antiqua#English Lyrics
Baltic's - http://hetalia.kitawiki.net/index.php?title=Peace_Sounds_Nice...#English Lyrics

9 tracks