I've found a web site that has line drawings of some military rockets. It's the James Madison University Center for International Stabilization and Recovery, Ordnance Identification Tool. It's aimed (bad pun) at helping to identify unexploded ordnance like land mines and other munitions. It has line drawings and cutaway diagrams of missiles to help identify them as well.

http://maic.jmu.edu/ordata/Mission.asp