Check your books for any signs of infestation. Droppings, tunnels, wings and other insect remains are clues that your collection is in trouble.
Identify the bug species that is infesting your books. Use a pest trap to catch a live specimen and save it so you can show it to an exterminator.
Take your bug to a local entomologist who will identify it for you. Contact the nearest university or college for help finding an entomologist, if necessary.
Seal the affected books in a plastic bag to prevent the infestation from spreading.
Find a professional fumigator who'll be able to deal with the infestation. Fumigation requires specific chemicals and controlled conditions, so it's best to leave it to a professional.
Take simple measures to prevent future infestations. Seal your library's windows, keep its humidity low and be sure to keep the shelves free of dirt and dust.