hi,
just wondering how much does it cost to list your site with google.

getting your site on google is free

if you have your site listed on another site you should get picked up

but theres no harm submitting your site manually anyways

http://www.google.com/addurl.html

Also don't forget to submit your site to other search engines also. Google will may pick it too.

The more search engines you submit your web site to better. Google has the lead for the most popular search engine, but if you are looking for traffic, you can still get a good amount of traffic from other search engines. If your web site deals with goods and services, then you should submit your web site to all search engines because it will increase your chances of making more money.