WP Google Maps is a plugin for WordPress by wpgmaps, there are free and Pro paid for versions.
Pro features include:
Add Descriptions, Links and Pictures to your markers
Create Multiple maps!
Let your users get Directions to your markers
Add Categories to your markers and dynamically filter them on your map
Mashup multiple maps
List your markers below your map
Export your markers to a CSV file for quick editing
Create a map and marker via custom fields
Add animations to your markers!
Fully responsive (mobile ready)
Use custom images for your marker icons
Add polygons and polylines to you map
Add Store Locator functionality to your map
Supports Fusion Tables
Latest Google Maps API
Drag and zoom to save your map location
Virtually unlimited markers
Free and Pro versions: http://www.wpgmaps.com