Roofing

National Roofing Contractors Association – http://www.nrca.net

Midwestern Roofing Contractors Association – http://www.mrca.org

Renewable Energy

Texas Renewable Energy Industries Association – http://www.treia.org

National Renewable Energy Lab – http://www.nrel.gov

Database of State Incentives for Renewables & Efficiency – http://www.dsireusa.org

North American Board of Certified Energy Practitioners – http://www.nabcep.org