I may not be the best person to reply because I have never used
lights to grow plants (yet), but I think the tube florescent lights would be the best way to go, compared to cfls (compact florescent lights). Assuming florescent lighting is what we are talking about, and not high energy discharge lighting ("HID"/MH and
hps). I was looking at some the other day, and was leaning toward the T8
bulbs. I think that would be the best bang for buck. The T 12's are cheaper, but put out less unsaleable light (lumen's). The particular T 12's I saw were 24 inch tubes, and put out 750 lumen's, the T 8's were also 24 inch but put out 1250 lumen's, and were only 2 dollars more (at about $10).
The light fixtures were not that much either, running about $12 and held between 2 and 4 tubes. Just make sure you get a fixture that's for the right bulb (T12/T8), their not interchangeable. Otherwise you need to exchange them for the right ones, or swap out the ballasts. These prices were at ACE hardware, and in my experience Lowe's and Home Depot are generally cheaper on just about everything.