title: How can I click on a button without an ID
body: <p>I'm using VB.Net and i'm using 
  <code>WebBrowser1.Document.GetElementById("submit").InvokeMember("click")</code></p>
  
  <p>But I can't seem to find the actual ID. I'm trying to find the sign in button id from the site: <a href="http://grooveshark.com/#!/login" rel="nofollow">http://grooveshark.com/#!/login</a></p>
  
  <p>Any solutions?</p>