its pretty easy to do that. 
You would want to use sub EVENT ITEM for the item handin, and a sub event say for the hail part:
so it would look something liek this:
	Code:
	sub EVENT_SAY {
if ($text =~/hail/i) {
	quest::say("Sorry $name i wont talk to you unless you have something for me");
	}
}
sub EVENT_ITEM {
if (plugin::check_handin(\%itemcount, XXXX => 1)) { #checks item, XXXX = item_id, and the => points to the # of items, so => 2, would be two of the items etc
	quest::summonitem(xxxx); #item id that was turned in, to return, i think you can use plugin::return_items(\%itemcount) as well
	quest::assigntask(xx); #task id goes in XX
	}
}
 As far as programs for task editing, i know there are a few out there, PEQ Editor will allow you to create tasks, and there also a program called TaskMaster that i used, i know its buried around here on the forums thats worth checking, worked well for me.