Answer:
if you do not speak fluent Chinese, get a Chinese friend to buy the tickets for you. if you try to purchase them on an English website they will charge you a ridiculous amount over than if you use a Chinese website. keep in mind that from shanghai to macau will be considered an international flight. same as hong kong. hong kong and macau will therefore cost you more than say... shenzhen. im sorry i can only give you a rough estimate. could be anywhere from 1500-3500 rmb depending on date, airline, to and from, and availability.