rossv what kind of lighting you looking for there are many kinds:
T5HO
MH
VHO
PC
....and the list goes on I hear alot of good things on T5 lighting. If you plan on having
LPS and
SPS then lighting is a must, if its all fish tank not quite of a concern. I have just ordered 2 T5HO light fixtures from SKR lighting. At a resonable price (very resonable)

What size tank do you have? Alot of the times if your
DIY lighting buy the parts that you would need will cost you just as much as buying a fixture or retro-fit.
www.hellolights.com is a great site, but they dont have resonable prices on just
DIY parts. If you have any more questions on lighting dont be shy to give me a private message ill be glad to help!