I would like it to be Florence and the Machine’s Howl. Because I am really liking her album right now.
“Now there’s no holding back, I’m making to attack
My blood is singing with your voice, I want to pour it out
The saints can’t help me now, the ropes have been unbound
I hunt for you with bloodied feet across the hallow’ed ground
Like some child possessed, the beast howls in my veins
I want to find you, tear out all of your tenderness
And howl, howl
Howl, howl
Hungry like the Wolf by David Cook has its possibilities..
In touch with the ground
I’m on the hunt, I’m after you
Smell like I sound, I’m lost in a crowd
And I’m hungry like the wolf
Straddle the line in discord and rhyme
I’m on the hunt, I’m after you
Mouth is alive with juices like wine
And I’m hungry like the wolf
Iced Earth’s Wolf
Innocence tainted by pure lunacy
Cursed by the slash of a shape-shifting beast
Oh no, this can’t be
Demonic infection, a doomed changeling
His future concealed as he begs to be told
A kiss from the gypsy, he’ll never grow old
Oh no, this can’t be
Demonic infection, a doomed changeling
As for a Goblin song. I initially thought ” We’re in the money” but if the goblins are being displaced from their home on the islands, then they probably won’t have much on them. So Money Money Money by ABBA would more appropriate because they would need to be thinking about getting more money.
Money, money, money
Must be funny
In the rich mans world
Money, money, money
Always sunny
In the rich mans world
Aha-ahaaa
All the things I could do
If I had a little money
Its a rich mans world
or even “If I were a rich man” – Fiddler on the roof?
If I were a rich man,
Ya ha deedle deedle, bubba bubba deedle deedle dum.
All day long I’d biddy biddy bum.
If I were a wealthy man.
I wouldn’t have to work hard.
Ya ha deedle deedle, bubba bubba deedle deedle dum.
If I were a biddy biddy rich,
Yidle-diddle-didle-didle man.
Or if they are really missing their home then My Island Homeby Christine Anu would be more appropriate
My island home My island home
My island home is waiting for me
In the evening the dry wind blows
From the hills and across the plains
I close my eyes and I am standing
In a boat on the sea again
And I’m holding a long turtle spear
And I feel I’m close now to where it must be
My island home is waiting for me
Provided by 
Pugnacious Priest's Warcraft Blog 
On a lighter note, you forgot Van Morrison’s “Moondance”
How about Men At Work – Land Down Under for the goblin theme song?
I came across a couple Florence and the Machine tracks this week and out of nowhere I’m really liking them as well. I got Dog Days are Over and a Leo Zero Remix of Rabbit Heart. I’m going to have to look into some more.
As for Worgen theme songs first thing that came to me when they announced the race was She Wolf by Shakira (I guess for female Worgen). I picture the transformation from human to worgen looks something like Shakira’s dance in the video.