Songr is a free desktop app that can find downloadable MP3s from multiple sources on the internet. In addition, it allows for a “lyrics search” option that can identify and download songs  based on parts of lyrics that a you might remember. It also can download YouTube videos or alternately only the audio part of a YouTube video as MP3.

Compatibility: Windows XP, Windows Vista, Windows 7. Requires Microsoft .NET Framework 3.5.

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