Fox Farm soil has nutes in it so you probably won't be needing any right away. I'd wait at least a week of them being in the soil and seeing how they do before using ferts. You can go Fox Farm for your ferts too, they're are pretty good. I'm currently using them. However I just ordered Neptune's Harvest Fish & Seaweed fertilizer, which I think is an even better option, because it's not likely to burn your plants and has incredible nutrients in there. I've been using their organic fish hydrolysate sampler and seriously feel it's one of the reasons my plants look so good. And...it's cheaper than Fox Farm!
http://www.amazon.com/Neptunes-Harvest-Organic-Seaweed-Fertilizer/dp/B0067CX2FU/ref=sr_1_7?ie=UTF8&qid=1338639711&sr=8-7
That link is by the quart, but you can order it by the ounce, pint, and gallon as well. I've spent a fair amount of my grow funds preparing for a dwc grow, but next time I set up a grow in my box, I'll probably just make my own soil with some organic soil without nutes, then mix it with bat & seabird guano, seaweed fertilizer, dolomite and a couple other things...then all you have to do for the entire grow is just water. No burning, no worrying about Ph, no deficiencies...can't get better than that! In the organic section, there's quite a few different organic recipes floating around. Something to consider for the future