Here is an interesting article on clothes moths:
http://www.epestsupply.com/moths.htm

Excerpt: "Clothes moth larvae are particularly damaging to fabrics stained with materials such as oil from human hair, human sweat, urine, beer, tomato juice, milk, and soft drinks. These caterpillars require a certain balance of nutrients in their diet to develop properly, and they especially need vitamin B. First instar larvae cannot survive on "clean" wool, but require the nutritional supplements found in soilage (body oils from the wearer of a garment)."

Cedar oil doesn't have much effect on adult moths, but can kill very young larvae.

Cedar tends to gradually lose its effectiveness against moths, and needs to be refreshed with cedar oil. You need to use the pure essential oil, not the thinned cedar oils you find in hardware stores. Look for what you need in shops that sell quality essential oils, such as aromatherapy shops. Paint it on the existing cedar boards, balls or cubes. The cedar wood can absorb quite a bit of the oil before it becomes oily to the touch.

There are also pheromone traps for certain types of moths. They just attract the males, but they will indicate that you do have a moth problem.

I know that most people dry-clean their woollens, but that stuff is toxic, and the shampoo & conditioner method has worked for me for about twenty years. I've used it for clothing, woollen underwear, and blankets. As long as you don't overheat the wool when drying, or keep it in the dryer too long, it works beautifully.

Sue