Adding icons to field labels
You can change the label using the template_preprocess_field hook.

For instance, if your field was named "phone" and the content type was "business", you could add this to your template.php:

template_preprocess_field (&amp;$variables) {
  $content_type = $variables['element']['#bundle'];
  $field_name = $variables['element']['#field_name'];

  if ($content_type == 'business' &amp;&amp; $field_name == 'phone') {
    $variables['label'] = '&lt;img src="http://www.carloancentre.ca/wp-content/uploads/2014/03/Contact-Methods-Phone-icon.png" height="16" width="16"/&gt;' . $variables['label'];
  }
}