I created 2 different wallets at block chain. The first one gave me an address for receiving btc. I used that address for a purchase, however, now when I login to my wallet, it no longer shows that address. Luckily, I saved it, and can search for it. It does show the btc I purchased, but requires me to enter the private key before moving them. I thought the entire address I sent for the btc included the private key. I also checked the other wallet I created, and the address I first got is not there either. These are the only 2 wallets I created and I know I received the original address from one of them. I know there are hackers out there, but that is not me. This is MY wallet, and I paid a lot of money for the btc, but clearly I screwed up somewhere. This is the address: 1593pt67xM8KRZ23Akxp2KwCj856fCfWSh
Your Bitcoin address and your private key are not the same.
The private key is a random number. You keep that number a secret, and only having it allows you to spend Bitcoins. It is used to sign transactions.
From the private key you derive a public key. It is used to show that you are using the correct private key. It is used to verify transaction signatures.
From the public key you can derive the Bitcoin address, which is a convenient way of encoding the public key. It is more compact, comes with error detection, and so forth. It is used to let people know where to send their Bitcoins to when sending you money.
From a private key you can derive the public key. From the public key - the Bitcoin address, but in neither of those cases can you do it in reverse. If you have lost your private key, your money is lost forever.
However, from what I can see your address has been successfully used for withdrawals, and its balance is currently zero. If you have gotten it from blockchain.info eWallet, you probably should contact the owner of the site with your issues. In Bitcoin world, it is very hard to prove that you own an address without having a private key.
Are you saying you received a payment but don't see the address when viewing the Receive Money tab in Blockchain.info/wallet?
That can happen when the funds have been spent, as the address gets archived. Click the Archive sub-tab to see if the address appears there.
Also you can see all activity for your wallet by clicking the My Transactions main-tab near the top.