Well, I like what pretty much everyone has said above.
Just want to reiterate, as AJDrew suggests - use half strength of anything you buy (if feeding based on the packaging directions), you can always go up in nutrients if the plants are liking it and/or need it.
***Be careful not to overdo it or you will be searching the internet on how to flush (and I'm not talkin' toilets here)
Also, as Inedible mentioned - peppers and tomatoes grow incredibly similar, you can use any food from one to the other (for the most part, of course)
I use Floranova in my soil plants, very simple and ph balanced so there really isn't anything to worry about and not much to do besides just pouring the correct amount per volume of water. Floranova comes in two parts, one for vegging and one for fruiting.
If you have the time and desire, organic is great. But if you're like me and need healthy plants, but have a lot to do in life, I suggest an easy to use nutrient. The floranova is super easy to use and the set of veg/flower bottles lasts me all year.
What I do about the amounts... I bought an EC meter and read the ppm of the solution I mix up each time. If it is the first time feeding and the soil had been feeding the plant by itself for a while, I would go safe with around 500-700ppm. The most I would feed my plants at any given time is about 1300ppm (which is a lot if your soil already has nutes, but it isn't too much when the soil is already very low on nutes).
And again, like mentioned above, it will take some getting used to any which way you decide to feed your plants. But feeding is a must once your soil nutrition value fades. The best indicator is always the plant itself. Learn the plant language and all will be fine!
PS: I am not a spokesman for floranova... lol. I have just tried a lot of different brands and this fits my needs the best. You just need to find what fits YOUR needs now.