Hi there. I use Terro. Works great. It's syrupy stuff and you put some on a piece of paper, or whatever, and the ants circle around it and eat and eat and carry it home to their nests. Takes care of them for a good long while. I just had to put some out yesterday....my second round with the ants. Good luck! Oh, it also now comes in handy plastic containers that the ants walk into. Less chance of the pets stepping into it or eating it. Though my cats have never showed any interest in it.

http://www.terro.com/index.php