Check out http://songza.com/ - it's a searchable audio jukebox of RIAA content as streamed into the browser from YouTube's audio channel. As such, neither the metadata nor sound quality is as good as Mixturtle, but the breadth of content is better. Songza also finds other music files using http://skreemr.com/, an audio file search engine.

Another alternative is http://listen.grooveshark.com/

I only realized that Songza pulled from YouTube yesterday. Clever.

don't understand what the fuss is about, there are plenty of website like that around, in particular i use www.melodyshot.com, its the same concept, only difference is you can download and there a way way more results.