@noboks,
First: Bad idea. It's probably too late, and it's unlikely that anyone--especially you--will ever see this reply, but don't get a Hebrew tattoo. It will most likely go horribly wrong.
If, by some miracle, your girlfriend never got around to doing it but still wants to over a decade later, and you happen to see this in time, and you're going to ignore my above warning, then read on.
לינ(ד)זי או' בריאן. Only add the ד if she pronounces the D, i.e. "Lin-dzey".
Turn the phrase COUNTER-CLOCKWISE so the ל is on top of her spine and the ן is at its base. It would look much better if you also turned the letters themselves 90 degrees clockwise, such that the phrase would look normal when she lies on her side.