DIY LED light kits?

[ceropegia]

Yesterday I purchased 4 new orchids at the Franklin Conservatory's annual orchid sale (including my first cymbidium! Yay!). All of the plants are extremely vigorous and healthy looking and I want them to stay that way. I've been thinking for a few months now that I want to add a new bank of lights to my shelf setup, and I think now might be the time to do it since all of the new orchids I purchased will require high light.

I've been looking at LED fixtures since I've heard a lot of good reviews about them, especially on their long life and energy efficiency. However as nearly-graduated college student these fixtures are pretty expensive for me, so I've been thinking about getting a DIY kit or assembling one from scratch (I have some tech-savvy friends who could help me out) to lessen the cost.

Has anyone here ever assembled their own LED light fixtures or purchased a kit? One other thing: I've read a lot of conflicting info about how far above the plants you need to hang fixtures, as well as how much area is covered by the lights. Can anyone give me some tips on this as well?