Programming a solution to know when a Bitcoin Address has stored a target amount Sorry, I'm probably not going to use the correct terms here.

Does anyone know of, or how to use bitcoind (or of an external library) that can look at or even provide event driven mechanisms to monitor when an address has received equal to or more than a target amount.

I know of the websocket API available from blockchain but I'd ideally do it in house using my own systems if possible.
A rough solution:

If the account is in your wallet, you can use:

bitcoind getreceivedbyaddress "ADDRESS"

to get the amount of bitcoins received by ADDRESS. You can put that line inside an infinite loop. You could create a shell program which stores the result in a variable every 30 seconds (using sleep) and compare it to the previous value. If you subtract the values and find a difference above a threshold you can make the script alert you. 

I can be more specific if you tell me your preferences (Python, Linux shell...)