Odd as I have a couple of machines running Win7 pro 64 and fritzing 0.9.3 and the search runs fine on both. As you note on start up it is greyed out, but clicking on the search arrow causes a brief red box in the main screen (a network update check perhaps?) and then the search bar becomes lit and works as expected. Perhaps something blocking the network access (assuming it is making one)?
Peter Van Epp