-get a tie rod puller for $20 or so from a cheap tool place (supercheap etc)
-get two hammers and hit the sides of the steering arms opposite each other at the same time (jars the taper loose). Then thread on the nut so that you will not damage the top of the tie rod end (if you are reusing it) and also to give a larger surface area to hit...I find placing a chock under the arm to stop it moving/locate it and then bashing the crap out of the nut works quite well If it still wont come, hit the sides some more, then try again...repeat as needed...