Thanks everyone for your help on this.

Ok, one last try here.

So I was able to find the following info on blockchain.info about the cashout transaction from Mt.Gox back in June, 2011

Original Mt.Gox transaction (cashout for 15 BTC)
https://blockchain.info/address/12Yim3HLs3vtpNonkSNN8WP6SiRL5svDeg

Unspent amount (14.9)
https://blockchain.info/unspent?active=12Yim3HLs3vtpNonkSNN8WP6SiRL5svDeg&format=html

So, If the bitcoins never made it to my wallet, is there any way I can re-capture them, or are they lost forever?

It appears that the transaction was never fully downloaded to the wallet.

Where would the private key for these bitcoins that were transfered exist if not in the wallet?

Yes, the harddrive is an ssd and has been my main machine being used on a daily basis.

I have tried both resyncing my bitcoin client and uploading what i think is the private key to a blockchain.info wallet i created. Neither of which show any record of the bitcoins.

I think it's safe to assume now, that the wallet.dat backup i'm using doesn't actually contain the correct private key, nor do i recall it ever showing up in my initial Bitcoin-qt wallet when i set it up 2 years ago.

Where can I look to retreive the actual transaction private key? Are they lost forever?

The private key is there in the output of my wallet.dat json export.

What should i do with it? Shouldn't Bitcoin-qt pick up on the private key and show my balance if it's valid?

Seems like maybe i don't have the version of the wallet.dat that fully received the transaction. In that case, what can i do?

I see my public address on blockchain.info.

Where can i find the associated private key and how do i re-claim them if they were never downloaded to my wallet?

The Gox withdrawl went to an address that shows up in my wallet.dat file in multiple locations.

If for some reason it didn't make it to this wallet ever, is there another way to recover the Bitcoins that were withdrawn from gox if i know the transaction address?

No transactions and no balance in my wallet. Only a receiving address with the MtGox Address.

I still have my Gox account.

I tried running the -rescan as you suggested, but still nothing is showing up afterwards (Zero balance in the wallet).

Is there any other way I can track down the intial cash-out transaction from Mt Gox to my wallet based on the address for it so I can see where the coins went?

I purchased some bitcoins back in June of 2011 and transfered them from Mt.Gox to a Bitcoin QT wallet for storage.

Since, sometime in 2012, i stupidly deleted my Bitcoin directory with the blockchain including the wallet.dat file!

I have since been able to recover the original wallet.dat file from August of 2011, which is 90kb and seems to contain the transaction receipt from the Mt.Gox bitcoin withdrawl.

I have now upgraded to the most recent bitcoin-qt client (v.0.85) and updated the entire blockchain with bootstrap.dat. Bitcoin-qt is telling me i am all up to date with the network, but my balance in my wallet shows up as zero. I do have the receipt address of the Mt.Gox transaction, but nothing in my 'transactions' tab.

So, I would like to know if anyone has any advice on recovering these bitcoins and how to proceed, thanks!