The AUX input on a Land Rover LR3 is located on the center console. It is at the back of the console, behind a cover that flips up. It is a standard 3.5mm stereo input like this stereo cable http://amzn.to/1Xo6wzO
I think the reason the input is back there is so the passengers in the 2nd row seats have access to the AUX input.
After owning the LR3 for a few years now, we have found that the location of the input is in a good place, it keeps the wires free of the dash.
A note on using the AUX function of the radio: The volume level is terrible, you have to crank the volume on the radio all the way up to hear the AUX.