Here is my lighting progress so far. The light bars are made from round and square brass tube soldered together. The lampshades are the Scale City 22" ones. The eBay LEDs are 0805 SMDs in warm white with the leads and dropping resistors pre-wired.
These are hung from the trusses:
I like to run buss bar for my structure lighting. Here is some 1/32" brass rod with some 1/16" brass tube to couple them together. I scuffed up the brass rod with some Scotchbrite to prep them for soldering the leads to. These trusses were CA'ed into place then pinned through using the method I described above.
I am undecided on how I will dress the wiring but I will most likely spray everything flat black and tuck the wiring up into the skylights. I may or may not add some more lights to the main section. Right now I have 8 total. Current car shop only has 6 and it looks OK.
Here's the little eBay power supply I will use. This one is being used by my machine shop that I just finished. It is adjustable from 1.2VDC to something way higher than I need using AC input power. I may use two, one for the main building and one for the machine shop extension so I can adjust the lighting for each section independently.