Assuming you have a Left Hand drive RAV, When sitting in the driver seat, put your hand on your Right knee. From your knee, move your hand to to inner center console. Now follow the crease between the center and the knee plate, and right after that plastic section ends, the port should be. It is White, so it is hard to miss. I'm sure someone on here has a pic in their album of the exact location.
If you do not have one, it is possible that your RAV is not equipped with one. I am pretty sure that all US Spec RAVs 96 and after were required to have the OBDII port, but I am not sure if it was a requirement elsewhere, or if it was included.