I am not there yet. But maybe you are. I do not have enough files stored on my Nokia N80 that I would need a search engine to find them. Still, Nokia announced that their Mobile Search application now also indexes local phone content.

The local phone search engine searches SMS, emails, calendar entries and files.

The Nokia Mobile Search still searches online resources as well, making it overall useful even if you do not need a local phone storage search engine.
Nokia Mobile Search works on the following Nokia phone models:
Nokia Mobile Search with My Content search supports the Nokia N95, Nokia N93i, Nokia N93, Nokia N92, Nokia N91, Nokia N91 8GB, Nokia N80 Internet Edition, Nokia N80, Nokia N76, Nokia N73 Music Edition, Nokia N71, Nokia E70, Nokia E62, Nokia E61, Nokia E60 and Nokia 3250 devices.

You can download the Nokia Mobile Search application for free here.