mmmmcake

Hello, I'm currently an undergrad studying the public's perception of recycled water. Would anyone know any services that would recruit survey participants for me, or sell me a database of people willing to participate? Ideally, I'd like a sample size of about 300-400 people from Atlanta, Georgia. So far, I only know about Knowledge Networks from my professor, and I'm not sure how reputable other services I've found on Google are. Any help is appreciated