Ok. I'm sure a few people could look this up quickly. But i will post it here also. How to get Onyxia key to Onyxia's lair. Ok here goes.
Step 1
Dragon Kin Menace
Helendis Riverhorn
Level 54 Burning Steppes
Obtained at level 48
Slay 15 Black Broodlings, 10 Black Dragonspawn, 4 Black Wyrmkin, and 1 black drake. Return to Helendis Riverhorn when the task is done.
http://www.thotbott.com/?qu=4182
Step 2
Travel to Lakeshire and deliver Helendis Riverhorns Letter to Magistrate Solomon
http://www.thotbott.com/?qu=4183
Step 3
Travel to Stormwind and deliver Solomons Plea to Highlord Bolvar Fordragon in Stormwind Keep
http://www.thotbott.com/?qu=4184
Step 4
Speak with Highlord Bolvar Fordragon after speaking with Lady Katrana Prestor
http://www.thotbott.com/?qu=4185
Step 5
Return to Magistrate Solomon in Lakeshire and deliver this Decree
http://www.thotbott.com/?qu=4185
Step 6
Go to Marshall Maxwell in Burning steppes and he is in Morgans Vigel there.
http://www.thotbott.com/?qu=4223
Step 7
Talk to Ragged John in Flames Creast in Burning Steppes
http://www.thotbott.com/?qu=4224
Step 8
Find Marshall Reginald Windsor in BRD -%26gt; he's in the right hand side jail loop you have to off killed the name in order to get the key to free him.
Step 9
Find a random drop In BRD called a 'Crumpled up Note' ive been told it drops of the dwarves outside the dungeon but i cannot confirm this.
Step 10
Return the Note to Marshall Windsor
He will now give a quest Shred of Hope.. Kill General Angerforge and Golem Lord Arglemach for 2 pieces of lost information. 'General Angerforge' is to the left of the area with the gnomes and golem lord is within the area with the gnomes. .. clear out the room before engaging Golem! Or he will call them to aid him. Return to Marshall windsor to begin the next part.
Step 11
Jailbreak! The most tiresome part as you have to clear BOTH jail loops and the whole center area of any mobs and also mobs will pop as you journey through. Also a few named encounters .. Keep windsor ALIVE until you clear both loops and find his friend Tobias.. talk to Windsor near the entrance once again and proceed to the next step
Step 12
Find Windsor in Morgans Vigel.. He wont be there. But the NPC 'forgot his name' will tell you that he has left for Stormwind.
Step 13
Go to stormwind and Run/Walk/Ride/Jump/crawl/skip/whatever out of the city for some distance then walk back. Windsor should be riding up. Talk to him then walk with him to the entrance of the keep. He will call you to gather an army for this part. 'It was solable until prepatch but i now here that is is possible to fail without a whole raid.
Step 14
Enter the keep. Watch hell break out loose or fight with a raid to maintain peace but normally Bolvar does all the work for you, all you do is hang in there and stay safe.. If your a rogue stealth 
Step 15
Take the fragments of the Dragons Eye to Kaleh in winterspring. 'Shes at the back off Mazorithill' . I suggest banking all of your and death hopping it to the back . Stand on the rune and you will be teleported to her.
Step 16
Venture up to Upper Black Rock Spire. And Slay Lord Drakasith and retrieve the blood of the black dragon champion
Step 17
Congrats you have your key for Onyxias Lair!
Hope this helped, its not that detailed. I could only give out some from thotbott because i couldnt find the others. This if for ALLIANCE. Hope this helps some of you. Any comments for the guide from anyone? 
Cheers
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