In DC Special #29, the origin of the Justice Society of America, a British agent tells the President: "We have received information—very reliable information, obtained at the cost of many lives—and it is now clear that Hitler plans to invade England—within weeks!"
The page quote comes from Return of the Jedi, when Rebel leader Mon Mothma points out many Bothan spies had died to bring the information during the briefing for the Battle of Endor. And only succeeded because the Emperor allowed it, or so he says.
In The Rocketeer, when Howard Hughes shows Cliff the Nazi propaganda film, he says "Keep watching, kid. It cost a man's life to get this out of Germany."
Happens in The Right Stuff, while the two White House staffers are showing the film of the Soviet space program.
White House Staffer #1: This footage was assembled from souces operating under cover at great risk.
White House Staffer #2:Very great.
White House Staffer #1: We're fortunate this material didn't perish... with a couple of men.
Christopher Walken's butt-smuggled wristwatch from Pulp Fiction.
The crew of a hovercraft, the Osiris, dies in a Heroic Sacrifice to warn of an impending Machine invasion against Zion in "Final Flight of the Osiris," a digitally animated short story from The Animatrix. This adventure is canonically noted at the start of The Matrix Reloaded when Niobe, a hovercraft captain, presents the Osiris's information for all to see at a captain's meeting.
Invoked in Babylon 5: Sheridan orders the Rangers to leak some information to the Shadows. However he is concerned that they won't believe it unless someone was...
Sheridan: "...willing to fight for it, willing to..." (he can't bring himself to say "die" in front of the very man he is ordering to his death)
In Star Trek: Deep Space Nine, Sisko and Garak hatch a plan to bring the Romulans into the war against the Dominion. One of Garak's contacts forges a data rod showing the Dominion leaders planning to invade Romulus, and Garak suggests Sisko tell the ambassador people died retrieving the data. The ambassador sees through the forgery, but Garak assassinates him and implicates the Dominion, which was his back-up plan the whole time.
Shepard recruits Tali in Mass Effect 2 after rescuing her from an important surveying mission gone south. Tali's entire squad (aside from herself and possibly one other soldier) is lost getting the data, which concerns a star destabilizing much faster than it ought to be.
Tali: That damn data had better be worth it. It wasn't.
While not exactly information useful at the time, this image◊ was taken when a Japanese bomb hit the deck of the USS Enterprise (CV-6). The Navy Photographer that took the photo was killed in the explosion, but the camera, and film survived, and can now be seen in many history books on World War II, particularly during the Battle of the Solomons.
Many Died To Bring This, High Bodycount Information Retrieval