In a number of recent articles, where I've interviewed some of social media's rising stars such as Jason Stone from Millionaire Mentor, Sean Perelstein, who built StingHD into a global brand and Nathan Chan from Foundr Magazine, amongst several others, it's quite clear that multi-million-dollar businesses can be built on the backs of wildly-popular social media channels and platforms.
Business address listings on Google, Yelp, LinkedIn, Facebook, Yellow Pages, and elsewhere count as backlinks. Perhaps more importantly, they also go a long ways towards helping customers find your business! There are many, many such sites. A good way to approach this once you've gotten the biggies out of the way - Google should be your first priority - is to make a point of setting up a couple new citation profiles every week or so. Search around for updated lists of reputable business listing sites, and use it as a checklist.
Getting unique and authoritative links is crucial for higher ranking in the SERPs and improving your SEO. Google's algorithm on evaluation of links evolved in recent years creating a more challenging process now to get high quality backlinks. External links still matter and aren’t obsolete, so start working on strategies to get valuable backlinks to improve your search visibility.