Centre for the Protection of the National Infrastructure
http://www.cpni.gov.uk

Carnegie Mellon CERT Coordination Centre
http://www.cert.org

Trusted Introducer for CSIRTS in Europe
http://www.ti.terena.nl

Forum of Incident Response & Security Teams
http://www.first.org

United States Computer Emergency Readiness Team
http://www.uscert.gov

Warning, advice and reporting point (WARP)
http://www.warp.gov.uk