Expanding on my comment
Fishing from a kayak is not really that much different from fishing from any other watercraft. You have less space to work with, like fishing from a Personal Water Craft, but it's certainly doable.
If you plan to do a serious amount of fishing from your kayak, or plan to be out for very long, or plan to be in rough water, there are some great add-ons you can get for your boat.

(Via South TX Kayak)
But honestly, though, in most situations, all you really need is your kayak and your rod. You can use a stringer tied to a cleat on the boat to keep the fish you catch, or you can convert one of the storage compartments or even an ice chest to a live well by filling it with water. Other than that, just get out there and have fun.

(Via South TX Kayak)