Greetings :wave: Did you know you can add soundfiles to a macro? go to PlaySoundFile macros - WoWWiki - Your guide to the World of Warcraft there you can find tons of soundfiles to macros.
SO HOW THIS WORK?!?!?o.O!!
Well you copy paste a sound file from the website to a macro and when u press the macro it creates a sound 
You can also make a class-related spell macro with a sound file examples are below:
Death knight:
#Showtooltip Army of the dead
/cast Army of the dead
/script PlaySoundFile("Sound\\Creature\\HeadlessHorseman\\Horseman_Special_01.wav")
/y SOLDIERS ARISE, STAND AND FIGHT! BRING VICTORY AT LAST TO THIS FALLEN KNIGHT!
This macro casts army of the dead spell, executes a soundfile from headless horseman and sends out /yell message 
Druid, balance:
#showtooltip starfall
/cast starfall
/script PlaySoundFile("Sound\\Creature\\AlgalonTheObserver\\UR_Algalon_Adds01.wav")
/y The stars come to my aid!
This macro casts starfall, executes soundfile from algalon the observer and sends out /yell message
Other cool macros are listed below:
HTML Code:
/point
/script PlaySoundFile("Sound\\Creature\\CThun\\CThunYouWillDIe.wav")
HTML Code:
#showtooltip [your stunning/interrupting spell here]
/cast [your stunning/interrupting spell here]
/script PlaySoundFile("Sound\\Creature\\YoggSaron\\UR_YoggSaron_Slay01.wav")
you can also replace the above soundfile with this:
HTML Code:
/script PlaySoundFile("Sound\\Creature\\Jaraxxus\\CR_Jaraxxus_Beserk02.wav")
Warrior
HTML Code:
#showtooltip battle shout
/cast battle shout
/script PlaySoundFile("Sound\\Creature\\Hodir\\UR_Hodir_Stalactite01.wav")
These are just examples, theres almost endless possibilities with these 
Hints and tips
The soundfile is client side only
Dont put soundfiles to spells that you use very often (like sinister strike) because if u spam it the sound plays many times wich is annyoing in some cases
6):
:wave: Hope you liked my first guide! :wave: