These pinging services will send out a ping to many of the popular blog directories so that you don’t have to go out to each one manually. That way you can concentrate on your blogging and making money.
There are several free services out there: pingomatic, pingoat.net, pingmyblog, and pingler.
Pingler particularly has a couple of good options. They have a free service for you to ping 88 sites that you can use manually. However, if you own several sites and want to automate the process, they also have a subscription service for $2.99 a month. You can register 25 sites with them and they will automatically ping your sites every 3 days. If you have that kind of volume, the service is invaluable.
in addition, if you like their service, you can sign up for their affiliate program and recommend them to others.
Making sure that you ping directories with your updates is a good free way to keep the blog directories up to date. This will gradually lead to more traffic for your site.