Hi, after recently leveling a paladin 1-83 as holy then switching to prot I found it annoying having to look up for sacred duty buff every time I had 3 stacks of holy power so I decided to edit around an addon I had. (Full credit for original addon goes to Midna and his track predators swiftness addon.)
You can use this to track a trinket proc, talent proc or any form of proc you need it to track that is not done already by blizzards power auras.
In the end it will look something like this: Tracking Sacred Duty on my prot pally alt.
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What you are going to want to do is make a new folder in your wow addons folder e.g. "C:\Program Files\World of Warcraft\Interface\AddOns\"
Now make two new text files and name the folder what you would like your addon to be called, I named mine "SacredDuty". Open up text file one and paste in this code.
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Code:
local active = false
local frame=CreateFrame("FRAME")
frame:SetScript('OnEvent',function()
local found=0
for i=1,40 do
local _,_,_,_,_,_,_,_,_,_,id=UnitAura("Player",i)
if id==85433 then -- 85433 = Sacred Duty
SpellActivationOverlay_ShowOverlay(SpellActivationOverlayFrame,85433,"TEXTURES\\SPELLACTIVATIONOVERLAYS\\FURY_OF_STORMRAGE.BLP","TOP",1,255,255,255,false,false)
found=1
end
end
if found==0 then SpellActivationOverlay_HideOverlays(SpellActivationOverlayFrame,85433)
end
end)
if UnitClass("PLAYER") == "Paladin" then
frame:RegisterEvent("UNIT_AURA")
active = true
end
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Now I have underlined what you are going to change.

For Blue You are going to want to go to Wowhead: That's a 50 DKP plus! Now search for your trinket effect/proc effect or whatever you want to track. Now copy the number at the end of your link e.g. for sacred duty "http://www.wowhead.com/spell=85433" and change all of the blue underlined numbers to your proc.
For Red It is quite self explanatory, just change it to the class you plan to track the desired proc.
Now save it as "AddonName.LUA", Of course changing AddonName to the same name as your folder.
Now open up Text file number Two and paste in this code:
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Code:
## Interface: 40200
## Title: SacredDuty
## Notes: Sacred Duty Tracking.
SacredDuty.LUA
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Interface is the current wow version to keep the addon up to date.
The title will be what it will be named in your addon list in game.
Notes will be what it says when you scroll over it.
Then at the bottom you will type what you called your previous text file.
Save this text file as AddonName.TOC
You are good to go 
You can change the green wave to other textures if you want but that's all up to you. Enjoy and have fun