If you want a decent search bar, go to
www.google.com and load theirs.. it
can be customized for your country of origin to some degree..
If you want a search bar that is invasive, spyware/adware is easy enough to
find.. Smiley Central, Comet Cursors or anything like that will ensure that
you get a 'search bar from hell'.. all you have to do is accept the sponsor
stuff that comes with them, and you can have hours of fun looking for ways
to remove them because your system has been reduced to a few kilos of
electronic scrap..
Stick with the Google bar, and don't be afraid to load the 'advanced' bar..
I know that some will argue that point, but it is ok really..