One source for Google search alternatives is alternativeTo. The listings come from people on the Internet, using sites, services, and software and deciding which they like to use best. (Of course, software developers, businesses, and marketers are also free to post on the site too). Overall, the alternativeTo site is not so popular that marketers have flooded it with junk. So, the site is a really good source for software reviews and alternatives to try.
A few to get you started: