[custom button] how to get a button with text clicable?

<span id="mybutton"  class="emulButton"  onclick="Action();"  onmouseover="mouseOver();" onmouseout="mouseOut();" >

how to associate a button

var oCorrectItem = new FCKToolbarButton ('My_Button', "tooltip");
var SEP = "/";
oCorrectItem.IconPath = FCKPlugins.Items['myplugin'].Path + 'img' + SEP + 'ico_plug1.gif';