|The Hong Kong International Airport Hotels|
Both of the on site hotels are near the loop road on the bottom third of this picture and they are both very expensive. The only other choice for accommodation on airport property is the in-terminal lounge which is open 24 hours and serves food and offers massage. It has small rooms and offers hourly and daily room rates.
Be very careful if you're shopping online for a hotel near the airport. The Hong Kong airport is located on Lantau Island near Tung Chung yet hotels as far away as Kowloon and Hong Kong Island will pay to have themselves listed as airport hotels. While it is not difficult to get into Kowloon or Hong Kong island on the bus or MTR subway service, (both of which run to HKIA) finding a 40 minute bus ride on the end of a 17 hour flight can be a rude surprise.
I would make one of two choices. If I wanted to stay near the airport, I would get a hotel in Tung Chung, there are many, or, if I was vacationing in Hong Kong, I would leave the airport behind and take the bus on in to a guest house in Kowloon. Good luck!