These 4 websites seem to be using the same script to talk to Googlemaps and house a database of nationwide stores.

http://www.findmymeds.com/
http://legalmarijuanadispensary.com/
http://www.mymarijuanacommunity.com./business-listings
http://www.mosthi.com/mmjlistings.html?i=32

Do you have any idea where I can find this script or plugin?

Thanks in advance for your valuable time, energy and support.

These 4 websites seem to be using the same script to talk to Googlemaps and house a database of nationwide stores.

http://www.findmymeds.com/
http://legalmarijuanadispensary.com/
http://www.mymarijuanacommunity.com./business-listings
http://www.mosthi.com/mmjlistings.html?i=32

Do you have any idea where I can find this script or plugin?

Thanks in advance for your valuable time, energy and support.

Google Maps API (http://lmgtfy.com/?q=Google+Maps+API)

The Google Maps API is everything you need to interact with Google Maps. There are several examples and suggestions for dealing with a large amount of pins as well.