Unconscious cover.

Huntress is being restrained by her enemy. After some lecture by another villain, the enemy behind her hits her in the head. Apparently she's unconscious when they take her to the car outside, because one of them comments about her waking up later.

Black Canary is running from a couple of enemies when she thinks she meets Superman, Batman and Mary Marvel. They however, turn out the be an imposter who knocks out Black Canary by hitting her in the face with a stick.

A nice cover of Birds of Prey - Manhunt issue 4. Black Canary is fighting Shiva while Catwoman and Huntress lie unconscious in the background.

Comissioner Amy Angotti, Ex Machina, and several other characters from the series have their mouths symbolically taped shut by Padilla, a cut throat reporter. Source: http://i.newsarama.com/preview_images/dcnew/sept09/7/exmachina_45.jpg

April O'Neil is knocked out from behind while on an archeological mission. She is tied to and alter and nearly sacrificed. Contributed by: http://s1.zetaboards.com/Everyone_In_Distress (hypermagneto999)

These are some Darna pinups I found on the net. I think they are fairly recent.

A very famous bondage cover by Alex Schomberg.

From the backpages of the issue. Published by Dark Horse.

Unconscious cover. I believe this is a one-shot. Nothing on the inside.

From Better Publications. Just some various scans.

Yellojacket is knocked out by a richocheting rock.

Cover from the Ultron Unlimited saga.

Roxy is knocked out twice. Both times are by head KO's.

IN the first scene, Roxy gets captured by a mad scientist via an implied injection (it's not shown). Caitlin Fairchild is later kidnapped by the same mad scientist. She gets injected from behind and passes out. All in all a pretty decent scene!

A girl is hit over the head. I am not sure what happens next, but she probably appears later in the story.

A woman with electrical powers zap a girl with a gun.

Erha is knocked out in an aircraft crash.

A woman is drugged via an injection gun.