"He drove a fist into her solar plexus and knocked the air out of her, shut her up." - Heart-Shaped Box by Joe Hill
"I dropped back down, my breath gone; then his steel toe kissed my solar plexus." - Step on a Crack by James Patterson and Michael Ledwidge
"Gabriel struck him again, this time in the solar plexus." - The Secret Servant by Daniel Silva
"Bourne grabbed the policeman’s pistol and drove another fist into the man’s solar plexus." - The Bourne Betrayal by Eric Van LustbaderOver at Bookgasm, someone noticed that characters are constantly getting hit in the solar plexus. You can find lots more solar plexamples there.