set template based on node field

gistfile1.php

<?php

function mytheme_alpha_preprocess_node(&$variables) {

  if ($variables['type'] == 'webform') {
    if ($variables['field_form_type'][0]['value'] == 'contact'){
      $variables['theme_hook_suggestions'][] = 'node__webform__contact';    
    }
    else if($variables['field_form_type'][0]['value'] == 'request'){
      $variables['theme_hook_suggestions'][] = 'node__webform__request';
    }
  }
}