Modify the default search engine URL in Firefox 1.5
Thu, Dec 29 '05 at 04:25AM • from: michaeldoc Web Browsers
If you have Firefox and like to use the built-in search engine, but find that it is not the appropriate engine for your home country (I am in Australia, so I like to use www.google.com.au rather than www.google.com), then the following will help you correct that problem.

To change the search engine URL ,you can open the folder that Firefox uses to store the search engine details and alter the .src file as follows:

1. Quit Firefox.
2. In the Finder, navigate to /Applications -> Firefox.app -> (Control-click and choose Show Package Contents) -> Contents -> MacOS -> searchplugins. This is where Firefox stores all its search engine files.
3. Find the relevant .src file (the .png and .gif files are icons) and make a backup copy (put the copy elsewhere).
4. Open the chosen .src file using the contextual menu's Open With -> Other option. Select any pure text editor (I used Text Edit).
5. Find the line that contains the URL (in google.src, it was the seventh line, which reads action="http://www.google.com/search and change it accordingly (to action="http://www.google.com.au/search in my case).
6. Reading the last line, updateCheckDays="1", I presumed that the engine might be updated automatically, so I changed this to "0", which I assume sets the updater not to update. This would prevent the hack being overwritten later, I guessed. Perhaps someone can tell me if this is so--I'm not sure if this bit is necessary or helpful.
7. Save the file.
8. Open Firefox and try out your new search engine.

This worked perfectly for me, but I am new to this sort of thing, so any comments or modifications would be appreciated