I've got a suggestion, "The Warlod" by Richard H. Dickinson. It's about a three star general who goes on a visit to Afghanistan, attends a meeting with local warlords, and all the problems that extend from that meeting. The plot is fairly typical, it plays out just the way you might think. What happens to, and between, the characters, on the other hand, isn't so typical and makes the book worth reading. It's a fast read, but it should provide you with some ideas for a campaign.
"I know twenty-six different points on your body I could hit and release enzymes into your brain to compel you to tell the truth -- Talk!"
Barry Ween, The Adventures of Barry Ween Boy Genius, Monkey Tales #3
Don Pendleton and the number of series he created or inspired are good places as well, perhaps. They are not always the best stories, but the ideas are usually pretty good and cover a range of topics.