Most of us only know LED light sources as little bright things that are in electronic components – or, if you’re in the industry, another low-energy consuming source that is getting brighter and brighter. I found a post at Madehow.com that lists the manufacturing process of “growing” LED lamps. I highly recommend reading it!
There is also a solid post at HowStuffWorks.com that goes into a little more basic detail. Check that one out too.