I like good tattoos, provided they aren't too masculine in appearance or location. Jailhouse tattoos and manly tattoos (ex. a skull/snake in the middle of the arm) are a huge turn-off. I love tattoos for myself, mostly because they help cover-up my freckles, which I am convinced that women HATE.
Piercings can be okay. I'm not into eyebrows, lips, too many in the earlobes, etc. Sometimes they can even look good enough to desire a quick fling with a chick, but I could never see myself dating a girl like that. I'm indifferent on nipple piercings or clit rings, I'd just as soon not have them there, but they're not a turn-off. I've never been with a girl with a tongue piercing. I imagine I wouldn't mind the practical pleasurable aspects of it, but they're so hazardous to your teeth and enamel that I'd never encourage anyone to get one.
The ultimate is a hot chick with a belly-button ring, though there is nothing nastier than a chick that does NOT have the body for one proudly displaying it. Show me a girl with a nice stomach walking around with a belly-button ring and I'll have the instant 80% erection, though the food court frowns on me jelqing in public. :D