Capital DEL (departmental expenditure limits) for 2008-09, 2009-10 and 2010-11 were set at the 2007 Comprehensive Spending Review. The latest Capital DEL tables, including figures for the Northern Ireland Office, are published on page 214 of the pre-Budget report in November 2008:
http://www.hm-treasury.gov.uk
The Government have not set departments’ Capital DEL budgets for years beyond 2010-11. Capital DEL budgets for 2011-12 and beyond are a matter for the next spending review. The Government do, however, publish projections for PSNI (Public Sector Net Investment) over the forecast period at Budgets and pre-Budget reports.