try either: a deepstriking suit or 2 with plasma, fusion, multi or else 1 or 2 deepstriking gun drone squads. if hes in a unit he wont be able to use fury of the ancients (from your first post it sounds like he does) because it cant pass trough his own units and if hes out of a unit use the deepstrike mentioned above. do you play mech or static? what sort of army does he use? are you only looking for anti librarian tactics?
ps: never rely on statistics but remember its 9 pulse shots to kill a marine and twice that to kill a terminator (so 36 pulse shots to kill a 2 wound terminator armour model)