Blog and Ping Networks
Here’s a list of networks that will Ping individual sites automatically for you.
If you use Wordpress just login to the control panel and then click options–>writing and then copy and paste these URLs near the bottom where it says “Update Services:
http://rpc.pingomatic.com/
http://pingoat.com/goat/RPC2
http://rpc.blogrolling.com/pinger/
http://ping.blo.gs/
http://rpc.weblogs.com/RPC2
http://ping.weblogalot.com/rpc.php
http://www.syndic8.com/xmlrpc.php
http://xping.pubsub.com/ping