Have you tried using the 55-200 that you already have for the product shots? You didn't say anything about what your product is, or how large, but I would think it would be good enough for this purpose. The lens focuses to 1.1m and gives a max magnification of 1:4. Even if you can't completely fill the frame, you have more than enough pixels to crop and still make a nice looking web image (the web does not require very high resolution images.) Of course, with an auxiliary close-up lens, you could get a little closer.
I take pictures of food for my wife's website, and I also take lots of pics for ebay. I have been using an 18-135mm nikkor and never felt the need for a macro. I always use a tripod, and usually set the lens to about 90mm or 100mm for a comfortable working distance. Of course, I do have to be mindful of the lens' minimum focusing distance.
I would be more concerned about the choice of lens for your daughter's ballet recitals. The 70-300 VR is an excellent lens for the money, but it is fairly slow which is not optimal for low light. You didn't say what your camera body is, but if you have one of the newer models with good high iso performance you could probably get away with it. Unfortunately, low light telephoto shots are one area where inexpensive lenses force you to make significant compromises.
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pschatz100
It's not how many pixels you have... but how you use them.