Well, I used the term "relay" to make it a little easier to understand initially. It is actually a rotating type of solenoid which has a physical interface that can be rotated by hand. Internally, the solenoid has extra contacts which can be used to display its position (position 1 or position 2). These contacts would come back to the Arduino to be displayed on the web page as status.
I would be using the latest Arduino with the Ethernet Shield which has the SD card slot. I imagine that we would use the SD card to hold the graphic images for the web page mimic display. This would be in case we would require more memory for the graphics than would be available on the Arduino.
I can write up a much more detailed listing of what must be done, along with some mimic graphics that would be used for the project, if you're truly interested.
Ed