Magento Rest API - oAuth Error

I am working with Magento Rest API for the first time, i went through the tutorials of Rest API on http://www.magentocommerce.com/api/rest and tried one example to fetch product through API:

$callbackUrl = "http://localhost/wineshop/products.php";
$temporaryCredentialsRequestUrl = "http://localhost/wineshop/oauth/initiate?     oauth_callback=" . urlencode($callbackUrl);
$adminAuthorizationUrl = 'http://localhost/wineshop/admin/oauth_authorize';
$accessTokenRequestUrl = 'http://localhost/wineshop/oauth/token';
$apiUrl = 'http://localhost/wineshop/api/rest';
$consumerKey = 'u48p1x9gzrg7r82c94woa5z7g805uw0i';
$consumerSecret = '96ydrk8s89xxath8h5z71vcl5abfq0zg';

session_start();
if (!isset($_GET['oauth_token']) && isset($_SESSION['state']) && $_SESSION['state'] == 1) {
$_SESSION['state'] = 0;
}
try {
$authType = ($_SESSION['state'] == 2) ? OAUTH_AUTH_TYPE_AUTHORIZATION : OAUTH_AUTH_TYPE_URI;
$oauthClient = new OAuth($consumerKey, $consumerSecret,  OAUTH_SIG_METHOD_HMACSHA1, $authType);
$oauthClient->enableDebug();

I've also installed the latest version of OAUTH and it also shows in my WampServer PHP Extensions but it doesn't show in phpinfo(). I coped the php_oauth.dll file into ..\www\bin\php\ext and i also edited php.ini and entered extension=php_oauth.dll but on running the products.php it shows me the

Fatal error: Class 'OAuth' not found in P:\wamp\www\products.php on line 19

And i also want to know that how to request for the token i've got key and secret after entering new consumer in Magento Admin Panel. But i don't know how to get Access Token & Access Token Secret that we enter in RESTClient

Please Help, Thanks in advance

reason for fatal error is oauth library is not installed. following step to install library

1) get the package from http://downloads.php.net/pierre/

2) search for oauth and choose the one for your machine

3) Put that .dll file in your PHP extensions directory.

4) Find the extensions area in your php.ini file and add this to it:

[PHP_OAUTH] extension=php_oauth.dll

restart your server

after solving fatal error if help is required then check http://www.magentocommerce.com/api/rest/introduction.html for magento REST API

use the sample code given in above link its is used for get Access Token & Access Token Secret etc. you have to just run php file