SimpleMap is a powerful and easy-to-use international store locator plugin. It has an intuitive interface and is completely customizable. Its search features make it easy for your users to find your locations quickly.

With SimpleMap, you can easily put a store locator on your WordPress site in seconds. Its intuitive interface makes it the easiest plugin of its kind to use, and the clean design means you’ll have a classy store locator that fits in perfectly with any WordPress theme.

Pricing: Free
Requirements: WordPress 2.8+
Source: http://wordpress.org/extend/plugins/simplemap/