Honey is chock-full of living critters including wild yeasts and bacteria. Boiling it drives off a lot of the volatile flavors and aromas, but not boiling it risks infection. You could pasteurize it, or you might just dump it in to your wort for the last few minutes of the boil, but you shouldn't put raw unpasteurized honey in your cooled wort.
Check out this Honey in Beer
PDF document that you can download from The National Honey Board
There's also a PDF document they provide that explains How to make Mead
Adding a bunch of honey to beer just ruins it, in my opinion. But that is clearly a matter of taste. Lots of people like it.