iTunes are one of the top online retailers of MP3s, iTunes was made famous as the free download software that supported the iPod. Since then iTunes has evolves to accommodate download games, podcasts, even download films. at iTunes there are over 3 million songs, 2,000 music videos, 35,000 podcasts and 12,000 audiobooks. Not exactly short on supply iTunes are constantly adding to this collection, and the store is designed to allow you to find the music you want easily and without long arduous searchs, naturally iTunes is totally legal and with relationships being built with key music producers you could soon get music direct from iTunes from bands and artists on the books of EMI and Warner. Check out iTunes here.
(Point to mention, clicking on the link opens your iTunes)