BBC Greek link Greek lessons from the BBC.
FSI Greek link The same course used by the U.S. government to train diplomats. This course is now available in digital format thanks to a community effort.
Learn Greek Online link Offers lessons for various levels. Free registration is required.
Learning Greek Podcast link Large free collection of Greek lessons in mp3 format with accompanying PDF files.
Mango Greek link A new website that offers Greek lessons. 100 lessons are currently available. Each lessons has accompanying audio. This is a great resource. Free registration is required.
Or try to find Pimsleur link Greek Lessons on P2P or torrent.
edit: changed a link, link to Mango is dead.