I found this site today by a mistake:
http://music.163.com/
It has one of the cleanest UIs around, great library of music (ranging from game OSTs I couldn't find absolutely anywhere to the classics) and it's pretty fast.
Being in Chinese sure is a disadventage, but I know absolutely none yet I still manage to browse through it just fine. There's search box (which you probably noticed), where you just input your search string, click the play button and that's it. It has greater functionality when you combine it with custom playlists (although for that you need a Chinese QQ account, I happened to have one from Blade & Soul, but I'm pretty sure you'll find guides on how to create one with a simple Google search), their PC client which lets you download the music itself (and which I absolutely recommend, even though the track loading seems a bit slower) as well as the android/iOS App that does the same thing as the PC client while looking incredibly clean and easy to use.
This is definitely going to be my only music solution for a while. What do you think?
Edit: In search results, the first tab seems to be the track list and the third tab the album list. I didn't need anything else so I have no clue what the others do.
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Currently busy working on a very large scale anime database project.