I have not used any lights for several years but it was my experience that using the least expensive 40 inch fluorescent and changing them often was more economical than buying a better light. For example back when I was using lights I could get four "cool white" for the price of one "grow light". I could not figure any way that the grow light was worth four times as much as the cool white.

You may find more recent information at the link below

Here is a link that might be useful: Gardenweb growing under lights forum

What Albert said. The main trick is to have the plants at as near the same height as possible and the lights just a few inches above them. I have had newly rooted roses make buds under a shop light set up like he described.