function createButton() {
    var a = document.createElement('a');
    var css = document.createElement('style');
    css.type = 'text/css';
    css.innerHTML = '#prt { position:absolute; right:3em; top: 6em; font-family: Arial,Helvetica,sans-serif; font-weight:bold; font-size:125%; background: #777777 none repeat scroll 0 0; color: white; padding: 6px 12px;}'
    a.href = '#';
    a.innerHTML = 'Print Topic';
    a.id = 'prt';
    a.onclick = getTopic; // DOESN'T WORK
    document.body.insertBefore(a, document.body.lastChild);
    document.body.appendChild(css);
}

a.setAttribute('onclick', function() { alert("hey"); });

element.addEventListener ('click', myClickHandler, false);

a.onclick = function(){
    getTopic();
}