I've just downloaded two songs but it seems to be that the song file doesen't provides any info about the artist, the name of the song, etc.
Is that normal?

depends whether the artists fill in id3 tags to the files. if they don't... that's too bad. for a fact, uploading an mp3 to this site will have the file name altered into a number, but id3 tags will be left intact. try to download a song of mine and you'll see that it works!

Thanks...