Fnd - Browse Apple App Store and iTunes on the Web
Just Install - just-install - The stupid package installer for Windows.
AppRecs - AppRecs sorts through reviews in the App Store and automatically helps you filter out inauthentic results.
Scoop - A command-line installer for Windows
Knicket App Search - The future Wikipedia for Apps
Windows Remix - Web-based batch software installer with zero dependencies. Recommended first visit after reinstalling Windows or buying a new laptop.