You've got to knock it loose first then unbolt the LCA ball joint to move the whole spindle assembly out of the way to actually remove the axle. You don't want to hammer directly onto the end of the axle. If you miss, you might be replacing wheel studs too and it is possible to mushroom the end and make it very hard to get out. You can either take a drift punch that fits in the center dimple or just a big block of wood (something like a foot long 4x4) and place that against the axle and give it a good whacking. Spray a little WD40 or the penatrating oil you have on hand onto the splines behind where the axle nut was removed and you should be alright.

To get the other side of the axle out, a large/strong flat head screwdriver between the tranny and the axle and a good smack with your hand will usually do the trick.