usestealth.com is a search engine that doesn't store any user identifiable information about the searcher. Consequently you can search for whatever you want and there is no way of tieing that information back to you. It runs searches on web, news, images and multimedia.
Unfortunately it's also very basic in the extreme - no advanced search, no help, no indication of the number of hits, and the display of results is limited. It's also shifted way over the right on my screen, which is quite disconcerting. However, if you're after a basic search engine that allows you to search incognito, this would do the job for you.