A few of the first grows I did was done with spending under $100 on lights. Just use CFL bulbs. They are everywhere and cheap. You could use CFL's through the entire grow cycle, but if you do that, you must boost the wattage of CFL lighting for the flowering cycle. Like lets say you you use 100W of CFL's to veg., it isn't recommended you use 100W to flower. The results will be weak, spindly buds. From 100W, you'd want to go to 200W, or at least 150W of the same lighting.

To get better results and spending a bit more cash, you could use CFL's to veg., and a small 150W HPS bulb for flowering, then you'd get some decent buds.

Like I said though, I used to use CFL's for one plant and got decent smoke. I used 85W of CFL to veg., and 125W CFDL to flower and got 1/4 yeilds from plants no bigger than a foot in height. Keep in mind it was in a very small space which makes a huge difference.

Good luck.