Google API & Wordpress developer

Developed a Wordpress site and I need someone with Google API experience - http://code.google.com/apis/ajax/playground/?exp=earth#changing_balloon_content - but basically - The path of the 80 days by Foggs - http://en.wikipedia.org/wiki/Around_the_World_in_Eighty_Days is to be done on a Google map - the user pays a donation via a query form and Paypal - updates the google map - with distance covered - if the user pays £100 then it will mark 100 metres on the map and show relevant details such as a logo, a comment. 

So in essence - the responsibilities is as follows

1 - Create a query form which asks for details (wp plugin contact form 7) will do the job. The user fills in the details then when filled up directs to Paypal - in which the donation is made.

2 - When the donation is successfully made then the google map will update with the logo / image of the company or person who filled in the details.

Thats it really.

Thanks - MC