Well, let me be the first to admitt that I am NO PRO. But, I have been doing this for a few years, and have read a ton. Basically you can veg 5 plants on a few 150w tubes (didn't know tubes came that high in w, you mean a cfl?), but the light spectrum which may be suitable for the plants to veg will not be correct for flowering. Also flouros, while I use them and like them, simply do not put out the lumens needed for proper plant growth. The biggest question in regards to lumens per plant is how big is your grow room? If you paint your walls flat white or use mylar, and grow in a compact area, then you might be able to work with two flouros. If you are trying this in a closet, where the light can "run-away" from your plants, then you will be under-lit.
Either way five plants is alot more of a realistic goal with Flouro's and it can be done. If I were to grow five, I would check out "SunBlaze." They sale 4' T5 HO full spectrum tubes for ~$34. Two or three of those should be able to definatly get you started. Good luck in your endevore, keep us posted.