Jane’s 360 http://www.janes.com has many reputable articles on the links between technology and warfare.

Aviation Week http://www.aviationweek.com/aw is another reputable website.

Global Security http://www.globalsecurity.org/military/systems/index.html also hosts articles on a range of technology issues, including valuable primers on the subject.

Military Technology http://www.monch.com/mpg/publications/military-technology.html has regular updates on recent developments in military technology.

Wired Danger Room http://www.wired.com/dangerroom has excellent reporting, particularly on cyber-related issues.