How do I find out if an address belongs to me 1CK6KHY6MHgYvmRQ4PAafKYDrg1ejbH1cE I believe is an old block chain address of mine
An address cannot 'belong to someone', but you could be in possession of the private key which allows you to spend from it. So if you have the private key (ie, you have access to the wallet that created that address, or a backup of it), then you can claim any coins held at that address.