Hi There,
Just wondering when you create a new BTC address via Bitcoin QT or some online website, can anyone see where that address was created, and where the coins are stored?
You can create a bitcoin address completely offline, and bitcoin can be "sent" to it. There is no location information encoded into the address itself.
Bitcoins only ever /exist/ as public knowledge on the blockchain, and are associated to new addresses by being signed over to new addresses from their previous addresses. It's like a giant public ledger. In this way, the coins are never stored in your wallet. Your wallet just contains the necessary information to sign transactions involving your addresses - e.g.: to spend your bitcoins you need information that's private in your wallet.
For ex.
If i send coins from gox address to bitstamp, can anyone find out that the funds have gone between these two sites? Address yes you can see that, but not sure about sites.
This example doesn't quite fit your first question. Because of the public nature of the blockchain, it's fairly easy through analysis to determine which addresses belong to major websites like mtgox.
