Do some research man.. there is SOOO much information by just using the search button.. or going on grow journals.. and looking at what people have.. you should find a grow journal from somone that only has a few plants.. see what lights they use.
It really depends on Space, availability of fresh air, safty, heat... etc.. you need to choose the light thats suit your grow environment...
But if your a newbie.. and growing in like a closet or somthing i would go with like 4-6 100watt + CFL's.... and buy some decent soil.. like FOXFARM and PH your water (most important) and you should be set.
Goodluck!