Android phones just aren’t very good media consumption devices yet. You’re mostly limited to buying songs from Amazon to play locally, or dragging your own MP3 files onto the device. Pandora and other services are great for radio (non-on demand music), and there’s a variety of paid streaming music services that you can choose from, with more coming soon (like MOG and Spotify). Google knows about this weakness, which is why they so strongly considered adding Spotify as a default app to Android.
If you don’t want to wait, and just want to stream music on demand right now for free, UMusic is a great choice. The app itself isn’t free – it’s $2 – but after you’ve purchased it there aren’t any more fees. All of the other streaming services on Android either charge or will charge per month once they launch.
Like a number of desktop websites, UMusic is grabbing songs from YouTube and stripping out the video. It works just fine, so long as Google doesn’t shut it down. And even if they do, you’ll likely get at least $2 worth of value before they do.
You find songs via search. The songs are automatically added to a playlist that you can later edit, and you can create new playlists as well to sort music. If the song is on YouTube, you’ll be able to find it on UMusic.