I think that in constantly fighting about whether these sorts of things are right or wrong is kind of lame ... Waheguru will love us nevertheless- whether or not we have a tattoo! Having a tattoo is not going to bring you any closer to Waheguru, nor will it pull you away.
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/hard-talk/2015-sikhism-and-tattoos.htmlReference:: Sikh Philosophy Network http://www.sikhphilosophy.net/showthread.php?t=2015
However, I just quickly want to give my little spin on it ... If the purpose of the tattoo is to inflate ones Ego (Ahankar), which, as most of you probably know is one of the 5 evils of Sikhism, then I am strictly against it. If however, it is an Ik Onkar, or a Khanda, that has tattoo'd on an easily seen part of your body, like your hand or something, which will remind you of god throughout the day, I don't see any problem with it. It'd serve a similar purpose as a Karaa, please correct me if I'm wrong.
Although, I was born into a Sikh family, they are not so religious. Nor am I, this is something I am working on at the moment, and am still hungry for greater knowledge, but from what I understand so far, there was my little opinion. Sorry, if I have annoyed anyone, my apologies in advance.
God Bless