Herbs as a Treatment for Bed Bugs

Are you aware of any herbal deterrent / treatment for bed bugs? Aside from the vacuuming, hot washing, steaming, is there an alternative to chemical treatment?
Do you know of any books on the subject - herbal insecticides (other than garden insects)?

Neem oil (a natural pesticide made from the neem tree) has shown effective in treating bedbug infested places. You can purchase Neem oil concentrate from Richters and follow the instructions on the bottle. Neem oil is harmless to humans and pets.
There is information on the Internet if you write - bedbugs, pesticide, herbs. Using the Neem oil might be the easiest solution, though.