The hotel @ abu dhabi airport has only has 40 rooms so you should ask your travel agent to book asap.  It is a nice hotel within the terminal so you don't have to worry about visa.  Check the tripadvisor link below to see some pictures.

http://www.tripadvisor.co.uk/Hotel_Review-g294013-d1210534-Reviews-Abu_Dhabi_Airport_Hotel-Abu_Dhabi.html

http://www.abudhabiairport.ae/services/accommodation.asp