Making some thing move twords something else?

then you should start working through some basic flash tutorials or hire someone to code this for you. you're undertaking a project that's beyond your current capability.

what don't you understand?

use a loop to update the screen objects. calculate the direction of the player's ship (using Math.atan2(playership._y-enemyship._y,playership._x-enemyship._x) to determine the direction).