I love tattoos (I have 5!) and I just couldn't and not to mention it here. I found several , but my favorite one is Alona Bondarenko's back tattoo. It looks really good on her!
Probably the most tattooed guy is Janko Tipsarevic. He has several of them.
Marat Safin (HOT!)
Flavio Saretta (I like his wrists tattoos)
Jurgen Melzer (this one on his back is really nice)
Juan Ignacio Chela (cute...)
Simone Bolelli (sorry I can't see it whole)
Amelie Mauresmo (pale!)
Mara Snatangelo (just great!)
Sesil Karatantcheva (nice)