'This is a question many Christians struggle with. I believe tattooing falls into the category of "disputable matters" where the Bible is not clear. But wait a minute, you might be thinking. The Bible says in Leviticus 19:28, "Do not cut your bodies for the dead, and do not mark your skin with tattoos. I am the Lord." (NLT) How much clearer can that be?
It's important, however, to look at the verse in context. This passage in Leviticus, including the surrounding text, is specifically dealing with the pagan religious rituals of the people living around the Israelites. God’s desire is to set his people apart from other cultures. The focus here is prohibiting worldly, heathen worship and witchcraft. God forbids his holy people to engage in idolatrous, pagan worship and sorcery which imitates the heathens. He does this out of protection, because he knows this will lead them away from the one true God.'
LINK: http://christianity.about.com/od/faqhelpdesk/f/tattoochristian.htm