GemWell I wouldn't say there is a "best" but each source has their own strengths.
I do highly suggest looking up the local new paper and business journal to see if they sell online ads. I can usually get a spot for $10-25 for an entire month depending on the size of the city.
From there be sure to drop a retargeting pixel and retarget everyone that views your ad and follow them around for a day on Facebook & Adwords