For some great info on skylights, you may wish to check out this GreenHomeGuide Q&A (here) by Cynthia Phakos.
With that said, if you are just looking for light I would recommend that you check out a product like SolaTube.
- Not only are these easier to install, but you can get around any obstructions in the attic while bringing in a great deal of light, even at night.
- Depending on the size it can also look like just any other recessed light and eliminates a lot of the insulation issues related to skylights.
I had a house in Phoenix where the kitchen was smack dab in the middle of the house with no windows and basically required a light to be on almost all the time anyone was in there. I installed two of the smaller SolaTubes and the change was remarkable. The most amazing part was that I could actually walk through the kitchen at night because it was picking up enough ambient light from outside to allow me to see.
No matter which option you pursue, consider the placements carefully and how the look / placement will affect your kitchen and existing items. That is one of the primary reasons I went with two smaller SolaTubes instead of just a larger one.
For more information:
Read "Are skylights a good idea? My partner says it will admit too much heat in the summer." a Q&A answered by Harris Woodward.