Found here : http://toolspot.org/script-to-get-shared-count.php API used here might be deprecated

Count tweets, likes, shares, etc

<?
class shareCount 
{
	private $url,$timeout;

	function __construct($url,$timeout=10) 
	{
		$this->url=rawurlencode($url);
		$this->timeout=$timeout;
	}

	function get_tweets()
	{ 
		$json_string = $this->file_get_contents_curl('http://urls.api.twitter.com/1/urls/count.json?url=' . $this->url);
		$json = json_decode($json_string, true);
		return isset($json['count'])?intval($json['count']):0;
	}

	function get_linkedin()
	{ 
		$json_string = $this->file_get_contents_curl("http://www.linkedin.com/countserv/count/share?url=$this->url&format=json");
		$json = json_decode($json_string, true);
		return isset($json['count'])?intval($json['count']):0;
	}

	function get_fb()
	{
		$json_string = $this->file_get_contents_curl('http://api.facebook.com/restserver.php?method=links.getStats&format=json&urls='.$this->url);
		$json = json_decode($json_string, true);
		return isset($json[0]['total_count'])?intval($json[0]['total_count']):0;
	}

	function get_plusones()
	{
		$curl = curl_init();
		curl_setopt($curl, CURLOPT_URL, "https://clients6.google.com/rpc");
		curl_setopt($curl, CURLOPT_POST, true);
		curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
		curl_setopt($curl, CURLOPT_POSTFIELDS, '[{"method":"pos.plusones.get","id":"p","params":{"nolog":true,"id":"'.rawurldecode($this->url).'","source":"widget","userId":"@viewer","groupId":"@self"},"jsonrpc":"2.0","key":"p","apiVersion":"v1"}]');
		curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
		curl_setopt($curl, CURLOPT_HTTPHEADER, array('Content-type: application/json'));
		$curl_results = curl_exec ($curl);
		curl_close ($curl);
		$json = json_decode($curl_results, true);
		return isset($json[0]['result']['metadata']['globalCounts']['count'])?intval( $json[0]['result']['metadata']['globalCounts']['count'] ):0;
	}

	function get_stumble()
	{
		$json_string = $this->file_get_contents_curl('http://www.stumbleupon.com/services/1.01/badge.getinfo?url='.$this->url);
		$json = json_decode($json_string, true);
		return isset($json['result']['views'])?intval($json['result']['views']):0;
	}

	function get_delicious()
	{
		$json_string = $this->file_get_contents_curl('http://feeds.delicious.com/v2/json/urlinfo/data?url='.$this->url);
		$json = json_decode($json_string, true);
		return isset($json[0]['total_posts'])?intval($json[0]['total_posts']):0;
	}

	function get_pinterest()
	{
		$return_data = $this->file_get_contents_curl('http://api.pinterest.com/v1/urls/count.json?url='.$this->url);
		$json_string = preg_replace('/^receiveCount\((.*)\)$/', "\\1", $return_data);
		$json = json_decode($json_string, true);
		return isset($json['count'])?intval($json['count']):0;
	}

	private function file_get_contents_curl($url)
	{
		$ch=curl_init();
		curl_setopt($ch, CURLOPT_URL, $url);
		curl_setopt($ch, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']);
		curl_setopt($ch, CURLOPT_FAILONERROR, 1);
		curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
		curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
		curl_setopt($ch, CURLOPT_TIMEOUT, $this->timeout);
		$cont = curl_exec($ch);
		if (curl_error($ch)) {
			die(curl_error($ch));
		}
		return $cont;
	}
}
?>

http://urls.api.twitter.com/1/urls/count.json?url=
http://www.linkedin.com/countserv/count/share?url=http://www.example.com&format=json
http://graph.facebook.com/?id=http://www.example.com

One of them screams "don't use my API !". Google !!!