Tattoos work by inserting ink into the dermis layer of your skin, changing the pigment. Usually this happens by taking a special gun that jabs a needle with color on it into your body, like, a gillion times a second. How much it hurts ranges anywhere from "exactly how much you are thinking" to "a lot."
List of Tattoo Shops in Olympia
Lit Fuse
Alley Cat
Spider Monkey
Fleshworks Tattoo