Autos are very easily available outside pf. But they always charge high. Just bargain properly. Otherwise if you can get local buses and sharing tempos at the g.t road which is just outside main entrance of station. The autos will take you to chherta,putlighar,khasa or sometimes end to wagah border. Buses also ply throughout the g.t road till atari.
And don't forget to try the tasty hot amritsari kulche chole. They are available through out near amritsar.