So you have a website up, and now you're waiting for visitors... and waiting... and waiting...
Time to find out if your site is indexed. To check it- go to Google or another Search Engine (SE) and in the search bar type:
site:www.mysite.com (replace "mysite" with your website name)
This will show you the pages that are indexed.
If you don't see any pages listed, well, you want to get the SE's to see it. You can go to all the search engines and click "Submit a site". This may take a long time to get listed because most submitted sites get "sandboxed" until the SE's decide that you're site isn't SPAM.
One of the best ways to get your site checked is get your webmaster to submit a SiteMap file to the SE's. This is a "map" of all of the pages on your site. Basically, you're saying "Hello Mr. Search Engine, here is my site and here is how to get around in it". Every time the SE's get their spider into the site, they'll look for the SiteMap file and will index your site with a little help from your Map.
Another way to get found is to get your website linked from another site that has been indexed. It might take posting your site in a forum (caution: read the forum rules before doing this because most have strict rules against this practice).
Yet another way is to get listed in a Directory. A Directory is a human-indexed search engine. Google, Yahoo, MSN, etc like to follow the links from these Directories because they know that they site has been checked by a human.
Of course, my clients don't need to worry about any of this, as I make sure they get indexed.