The first 2011 Census outputs for Northern Ireland were released on 16 July 2012.
Original NISRA First data release
The raw data (xls files below) and various support papers relating to the first release have been made available:
Individual 2011 Census tables:
|NI01 (xls)||Usual resident population by single year of age and sex||Northern Ireland|
|NI02 (xls)||Usual resident population / Households / Average household size||Northern Ireland|
More details are available from the NISRA website.