This plugin allows a WordPress Site Admin to enter locations of stores etc into the db. The information is then displayed on the front end 
using the google maps interface. The user can enter a starting location in the search field, the system will then find the closest location from 
it’s starting point and display the path and steps necessary to get to that location. If many locations are available in a similar range range, 
the plugin will request the driving distance between the two closest locations. It help to avoid the pitfall of getting an office across a river 
which may take a lot of driving to get to.
This plugin requires a valid Google Maps API key (free) from Google. If you do not have an API key you may get one here. 
http://code.google.com/apis/maps/signup.html
The actual google maps functionality is based on GoogleMapAPI – A library used for creating google maps. Which can be found here 
http://www.phpinsider.com/php/code/GoogleMapAPI/

GoogleMapper

This plugin allows a Wordpress Site Admin to enter locations of stores etc into the db.  The user can then search for the closest location.

plainware

Locatoraid is a lightweight, easy-to-use store locator plugin.
Let your customers find your stores, dealers, hotels, restaurants, ATMs, products, or any other types of locations. Autolocate visitor position to offer your nearest options.
Start In Minutes 
Just start adding your locations, then the automatic geocoding function finds the coordinates, and your locations are on the map waiting for your customers!
Custom Map Styles 
Easily configurable map styles to match your website.
Shortcode Parameters 
A number of <a href="https://www.locatoraid.com/shortcode-parameters/" rel="nofollow ugc">shortcode parameters</a> that can be used to configure the front end view, like default search text, search radius, view layout, limit to a state or a country, and more.
Works Worldwide 
More than 200 countries covered. USA, Australia, Canada, Hong Kong, Italy, Japan, Mexico, Singapore, South Africa, Spain, UK and more. As long as it is on the Google Maps, it will be found.
REST API 
The <a href="https://www.locatoraid.com/restful/" rel="nofollow ugc">REST API</a> lets you query and modify your locations through a number of REST endpoints.
Mobile Friendly 
Responsive design that works perfectly well for iPhone, Android, Blackberry, Windows as well as for desktops, laptops and tablets.
<h3>Pro Version Features</h3>
Bulk Upload and Export 
The <a href="https://www.locatoraid.com/upload-export/" rel="nofollow ugc">Bulk Upload and Export</a> module lets you import, export and update your locations with a CSV file.
Custom Fields 
Add up to 20 <a href="https://www.locatoraid.com/custom-fields/" rel="nofollow ugc">Custom Fields</a> to store and display additional information about your locations.
Products 
Assign <a href="https://www.locatoraid.com/products/" rel="nofollow ugc">Products</a> to categorize your locations.
Custom Map Icons 
With the <a href="https://www.locatoraid.com/custom-map-icons/" rel="nofollow ugc">Custom Map Icons</a> you can set any custom icon for any of your locations.
<a href="http://www.locatoraid.com/order/" rel="nofollow ugc">Get the Pro version of Locatoraid store locator plugin!</a>
<h3>Support</h3>
Please contact us at <a href="http://www.locatoraid.com/" rel="nofollow ugc">http://www.locatoraid.com/</a> 
<a href="https://www.facebook.com/Locatoraid-165233107413846/" rel="nofollow ugc">Follow on Facebook</a>
Author: Plainware 
Author URI: http://www.locatoraid.com

Locatoraid Store Locator

A lightweight, easy-to-use store locator plugin. Premium version adds CSV imports, custom fields, custom map markers, location categories and more.

GoogleMapper vs Locatoraid Store Locator