I know there are many PC members interested in LEDs. Digikey is a major distributer of electronics components, and they sometimes offer online training modules. This is link to module for Cree high power LEDs: http://digikey.com/PTM/PTMPartList.page?site=us〈=en&ptm=17633 The training module links are at the top of the page. The rest of the page is a listing of Cree parts. Tom