collect tweets and post to Google Map

Hi. I want code that will take tweets from Twitter, save them to either a database or a flat file and then using Google's geocoding api, get their location and then have them posted to a google map. I want to be able to filter the tweets that are posted to the map based on a keyword. The map, probably using AJAX, should be updated regularly (say every 10 seconds) with new tweets if there are new ones that contain the keyword. Looking for bids less than 100 dollars