Drupal 7 adding Google web fonts as external stylesheets

To use Google web fonts as external stylesheets to your theme, you cannot use the themes .info file. Instead you can add this in template.php. In Drupal 7, if you want to add the 'PT Sans' Google web font do this as follows:

<?php
function YourThemeName_preprocess_html(&$variables) {
drupal_add_css('http://fonts.googleapis.com/css?family=PT+Sans:400,700,400italic,700italic&subset=latin,cyrillic', array('type' => 'external'));
}
?>

After this addittion, just add the 'PT Sans' in your style.css file. For example

h1 { font-family: 'PT Sans',Helvetica,Sans-serif; }

If you want to add/load web fonts for a single page and not for the whole site, you can use drupal_add_css() and place a condition around it.