Looking for help with a script.
 

As I've already explored several addon options in this regard (some of which did not work at all; some did but had various other options I didn't want, etc.), I have taken it upon myself to look into creating my own script.

What I'm looking to do is as follows:
1. Summon my mount.
2. Mount finishes casting, buff appears in buff line, a specified sound is played.
3. I'm hoping to only achieve this with one particular mount in my roster.

The mount I'm hoping to exclusively single out, here, is the Red Drake (attained via the Wyrmrest Accord faction), and to play a particular sound file (which, currently, is an mp3, but I can always modify it it to other types) each time I summon it.

Could anyone point me in the right direction to accomplishing this?

http://wowprogramming.com/docs/events/UNIT_AURA
http://wowprogramming.com/docs/api/UnitBuff

If I understand correctly, you just want to play a sound file when mounting your red drake?

Just as a side note... only you will hear the sound. It could be made that so anyone who has your script can hear the sound but other wise only you will hear it. Also are you looking to make a button that mounts the red drake as well?