Browser Addon For Multiple Browsers

I require a simple addon to be written for the following browsers; IE7, IE8, Firefox 3.x, Chrome, Safari, Opera. I don't actually know if it's possible to write it in all of these, so if not, please tell me what is possible, and provide a quote for that. I also require for each some code that can be pasted on my website such that the user can install the addon with a single click (such as can be seen on the Mozilla and MS addons pages) ## Deliverables I require a simple addon to be written for the following browsers; IE7, IE8, Firefox 3.x, Chrome, Safari, Opera. I don't actually know if it's possible to write it in all of these, so if not, please tell me what is possible, and provide a quote for that. I also require for each some code that can be pasted on my website such that the user can install the addon with a single click (such as can be seen on the Mozilla and MS addons pages) It need to work on all versions of Windows from XP forward, and also on the Mac. Here is a description of the addon. When the users enters a search either in the search bar (in the tool bar) OR in the address bar, the user will go to my adsense for search search results. This can be done by directing to the following page (replace XXXX with the search term, with a space replaced by '+') [login to view URL] I would also like the user to be able to edit the settings such that they can select a different default country. Here are the different URLs for the different countries... US/World [login to view URL] UK [login to view URL] Canada [login to view URL] Australia [login to view URL] New Zealand [login to view URL] Ireland [login to view URL] South Africa [login to view URL] Germany [login to view URL] Many more countries will be added in the future, so please make this easily scalable. Part of the deliverables of this project include showing me how to add more countries. If possible, I would also like this addon to call home to check for updates. I would need to be shown how to use this as well.