we have a list of locations in a mysql table, you can read them out via sql and display them on a google map with usual A-Z pins
then you can search as well in the locations we have based upon certain parameters, e.g. country, city, postcode and you will then refresh the map to display the list of locations matching the search criteria.
This search and refresh would be done via an ajax call to a server side script which gives you a json object, which you would need to write.
this is a very simple job, all details are given above we'll give you some specific data and user interface with the person we choose to work on this project.
don't bid above 30 as it's very simple list of tasks for anyone who has done this before.