u can buy Nikon D80 at CHUNG YUEN PRO SHOP; it's an authorized dealer of Nikon. salesman is very accomodating. price is also good.
u can also try BROADWAY (but price is slight higher than Chung Yuen), staff is also friendly.
in both stores, u can ask a lot of questions, see the item/product. very accomodating! unlike other camera stores near Kowloon Park.