SEO on a Database Driven Website

I have a question about a site I'm developing. It is a database driven directory site where people can make a profile and list themselves in one or many area codes and in one or many fields of work. When someone is looking for a person to hire, they enter one or more area codes to look in (or select them with checkboxes) and when the form submits, it saves these as a cookie so the site remembers what location you were searching in. You then narrow down your search by category and field (which are links) and get a listing of all the profiles that match your search.

What I am concerned about is this: because a search engine can't type in or select area codes to search in, how is it going to find and index any of the profile pages? It doesn't allow the user to search for people without first selecting an area code, because there's no practical purpose to do so. There would also be no practical purpose from a user experience/usability standpoint of simply having a list of each area code as a link to the categories page, but as far as I know, isn't that the only way for search engines to see every person?

How does a site like Facebook accomplish this? There isn't some sort of master d开发者_如何转开发irectory with a link to ever single Facebook user's profile page, and yet they're often the #1 search result for a person's name.

You can try to get some of your db driven pages indexed by doing the following:

Generate a list of links with area codes. It is better if they are pretty urls.

www.path.com/find.asp?areacode=707 // okay
www.path.com/find/areacode/707  //better

Add these links to a sitemap.xml and submit to Google. There is no guarantee that all of your area codes will be indexed. in fact only a portion will because google will see how similar they are.

Sitemaps are a way to tell Google about pages on your site we might not otherwise discover. In its simplest terms, a XML Sitemap—usually called Sitemap, with a capital S—is a list of the pages on your website. Creating and submitting a Sitemap helps make sure that Google knows about all the pages on your site, including URLs that may not be discoverable by Google's normal crawling process.