Here are my rules of thumb for tattoos. Please don't take any of this personally. I just feel that a tattoo is deeply personal, and not just an accessory like a hat or watch. You are permanently inking your body and others WILL judge you based on its appearance, location, message (if any), etc... trust me. You should be aware of all the good and bad things that can result from having tattoo and be ready to accept any, and all, consequences of your decision. That being said...
1) If you're unsure what to get, or whether it will be "cool" or not... don't get it.
2) If you are doing it for someone other than yourself... don't get it.
3) If you have any doubts... don't get it.
4) If you have to ask... definitely don't get it.
Now, when if & when you are ready. Flow Mike_D's advice... do your research, find a good artist, and spend some cash on it. Artists all have their strengths and weaknesses, so if you want a picture of your girl tattooed on your ass, don't hire the guy who's portfolio consists of only flowers, bunnies, and barbed wire. Lastly, if you do decide to get one in the end... good luck and I hope it works out for you.
There's two sides to every schwartz, he got the up side and I got the down side.