Please enjoy this article curated from Moz Local:

Local SEO Search the United States

There are four primary sources of data for all the major search engines: Infogroup, Acxiom, Localeze, and Factual. Other companies like Yellowpages.com, Citysearch, and Superpages.com can also play a role in this cycle, sending “fresh” feeds to the search engines every couple of months.

If your business information is incorrect at any of these major providers, it may override what the major search engines have in their own database. And if you're not included in the databases of these major providers, your business is not going to rank as well in Google, Yahoo, or Bing.

In addition to the major search engines, there are a myriad of secondary search engines that are also valuable in driving traffic to your website—and hopefully bringing you more business. Most of these secondary portals get their data from the exact same places that Google and Bing do—just one more reason you need to make sure your business information is correct at those handful of primary providers.
Major Data Providers: Who Powers Whom?
Localeze:

Yahoo Local (reference)
Bing Local (reference)
Twitter (reference)
Apple / Siri (reference)
Foursquare (Localeze source)
Facebook (reference)
Yellowpages.com (reference)
TripAdvisor (Localeze source)
Groupon (Localeze source)
Yellowbook (Localeze source)
Local.com (Localeze source)
DexKnows (reference)
Kudzu (reference)
GetFave.com (reference)
Best of the Web Local (reference)
YellowBot (reference)
MojoPages (Localeze source)
Amazon (reference)
Comcast (Localeze source)
Hotfrog (speculation)

Infogroup:

Google Maps (reference)
Mapquest (reference)
Bing Local (reference)
Yahoo Local (reference)
Citysearch / CityGrid (reference)
Twitter (reference)
Ask (reference)
AOL Local (reference)
Superpages.com (reference)
Yellowpages.com (reference)*
DexKnows (Infogroup source)
Yellowbook (Infogroup source)
Whitepages.com (reference)
TomTom (reference)

IAC properties / CityGrid:
http://citygridmedia.com/publishers/
Acxiom:

Yelp (reference)
Yellowpages.com (reference)
Superpages.com (reference retrieved 12/17/13)
Local.com (reference)
Yellowbook.com (reference)
Apple / Siri (reference)

Factual:

Yelp (reference)
Bing (reference)
TripAdvisor (reference)
Apple/Siri (reference)

All un-asterisked screenshots taken 10/01/2009. Asterisked screenshots taken 07/19/12.
Information from Localeze source provided 02/21/12.
Information from Infogroup source provided 07/19/12.