Here's my quick 2 cents:
All of the law was fulfilled in Jesus - we are not bound by the law in any way, including trimming our beards and getting tatoos. We are saved by Christ, it is grace, and we cannot do anything to deserve or earn it, nor can we do anything to keep or lose it.
Now we need to look at the heart of the issue. The Bible does not seem to forbid alcohol, yet it is clear on drunkenness being a sin. This issue for me looks like this:
In the OT, the Nazarites (people who took a special vow and consecrated themselves to God) were forbidden to touch any alcohol, grapes, their seeds or even the skins of the grapes - anything that could ferment. As I was meditating on this, it seemed that one of the reasons could be that if they were known for "dipping into the sauce" now and again, and they get this big revelation from God, it could be dismissed as "It looks like John was drinking too much communion wine again..."
The call of God was one of separation from the things that were acceptable for the majority, and a setting ones self toward God in a way that was also greater than the majority. It required sharp senses - anything that would dull the spirit was no longer acceptable, today it would look like getting rid of the things that waste your time and distract you from Jesus. It is on that basis that I will not drink alcohol - not because there is some "law" or rule against it, but rather it impedes my relationship and sensitivity to God. I am not content with an average or common spirituality - I need and want more, so I voluntarily lay down what is permissible to help me know Jesus in an increasingly more intimate way.
My perception on things like tatoos, whether certain types of music are inherintly evil, whether the theatre is an evil place and if it is ok to play cards (things that are not clearly set out in the Bible as sin, and in the case of tatoos, if you are going to follow that part of the law, you must follow the other rules regarding shaving etc.) comes down to this quote:
"This is how Susannah Wesley defined "sin" to her young son John Wesley:
Whatever weakens your reason, impairs the tenderness of your conscience, obscures your sense of God and takes off the relish of spiritual things, that to you is sin!"
There are other things to bear in mind with tatoos though.
I believe that when you allow someone to mark your body in a permanent fashion, you really need to be aware of the spiritual cleanliness of the one doing the tatooing. You do not want to come out of the tatoo parlour with a bunch of spiritual baggage that you will need to be delivered of later.
My wife wants to get a nose ring, but we only have really perverted slime ball piercing/tatooing places here, so we will need to go to another town to find a salon that will do it.
Hope that helps and raises some discussion...
