BTC-E can work thru webservers. It is an API as long as you can connect to the btc-e server you can run it. For a few bitcoins I can create a php library for you for btc-e.
I know all this... I'm simply stumped on how to execute the actual trade via the API. I'm not looking for someone to create an entire library for me, just point me in the right direction so I can do it myself.