My build for AD Poppy is typically straightforward. I play her as a very aggressive fighter. I get her a TriForce of course, with boots of mobility, as well as a Phantom Dancer, Infinity Edge/Blood Thirster, possibly another Phantom Dancer, and the last item is entirely situational. With all of these items her normal attacks crit for a for a lot of damage, her attack speed is magnificent, her Q hits like a monster, and she cannot be run away from, especially if combined with ghost and exhaust.
It's a very beaslty build, especially if the game ever goes long enough for you to finish it. You will find yourself joining fights and destroying any squishies around, as well as being able to go head up with any of the other team's DPS chars.