I would start by checking your business information online, "Business name" + "business phone number", to make sure that it's consistent across all citation sites. If not- time to clean it up and start with the main data aggregators like infogroup (expressupdateusa.com), Google Plus Local, MAP MAKER, Factual.com, and even Facebook.
Then move on to the sites like Yelp, Superpages, Citysearch, Insiderpages, Merchantcircle, etc. Most of these are review sites but I don't think that the fact that they are review sites makes them an influence. From my understanding Google is looking more at the information provided and not the # of reviews.
BUT, I do believe it is still important to get reviews on those smaller sites considering how often they seem to be dominating the SERP's lately.
New advertising option:
A review of your product or service posted by a Sterling Sky employee. This will also be shared on the Sterling Sky & LSF Twitter accounts, our Facebook group, LinkedIn, and both newsletters.