For a guy, I think the best place is the shoulder, upper arm, or the calf. This way it's not shown when you're dressed for work.
I know some places don't care about tattoos, but I've worked places where they say you have to cover your visible tattoos, which sucks when it's 100 degrees outside, and your tats are on your forearms. Personally, I think that's discrimination, but that's just my .02.
![Grin ;D](https://www.stonetemplepilots.nl/forum/core/Smileys/default/grin.gif)