I'll try
Method 1
Try taking two pic, one properly expose the night scene and the other one the moon, then usperimpose in photoshop.
Method 2
use a graduated filter (if you've one) to 'dim' down the moon.
Method 3
If exposure time is long (few sec) use black cloth to cover the top part of the lens for a while. This need to trial-by-error to perfect.