I would recommend a simple two or three part fert. when I first started growing all there really was, was General Hydroponics Grow, Micro, and Bloom. The dosages on the bottles actually taught me fairly well how to tailor my ferts to my different light cycles(veg and flower). I believe GH now makes a two part, grow and bloom formula, I know theres about 100 nute companies that have a two part fert.
try GH. they pretty much spell it out for you and its super inexpensive. You could add a couple supplements to it, but I would keep it simple for your first grow. People seem to think you need every supplement on the market, but I have seen pretty much Identical results with a simple, base formula. Hope that helps! Don't fret! Its just a weed...