Brian's Bee Butter from right here in Alabama:
http://www.carpenterbeesolutions.com/order-products-to-get-rid-of-carpenter-bees.html. Don't mess with the traps, they didn't work for me. The "bee butter" on the other hand will hammer them. It is basically permithrin mixed into some type of sticky Vaseline type product. Put a little in every hole you can find and have a back back blower ready the next morning if the crows or other birds don't get to them first. If not this then delta dust (deltamithrin) or seven dust into the hole. Nothing you spray on the surface of the wood is going to have that much affect on them because they aren't actually ingesting the wood and they only bore into a small spot, so not much contact with the product. The key, after the butter or dust treatment, is sealing all the holes. I usually stick a small piece of steel wool in them, wood putty, and stain. The steel wool keeps any that may hatch from eggs from coming back out. Then there are a couple water seal type products with repellents in them out that you can treat the wood with. I have done some side work for the last three years at a house that is redwood and cedar, so I have read about everything I could get my hands on about them. If you do have to surface spray, then Demon WSP seems to work the best and have the best residual, but you will still have to retreat every couple weeks or after a rain. Hope this helps. If not get a good tennis raquet and a six pack and do it the old fashioned way. Which, I guess would be cool again because it is "green friendly". Good luck.