I always recommend buying your music, it's cheap enough for a track from about 79p... I know most of those downloads are of artists that have earnt millions, but some of us struggle to earn a living from music sales.
I work many, many hours producing, remixing and recording vocalists for not alot of cash due to illegal downloads of my releases.
By no means am I having a go, but some artists only make a little for alot of work.
Apologies if you were looking for legal sites, and I will shut up now!