Googlebot will crawl your pages, as long as they have a link that is known to Google. Then Google will update their index, rank you, and include you at the appropriate spot. Sometimes they will crawl you fairly often; sometimes it takes quite a while.
If you have spent considerable time and resources updating and adding content to your site, you might want to consider a Google SiteMap. This won’t replace the spiders’ visits and any other modes of communication, but you can bump yourself up the list to get your improved site looked at.
You want to provide Google with the easiest, clearest route to what you want them to look at, so don’t clutter up your sitemap with stuff they don’t need. Leave off your doorway pages, any duplicated content and of course any pages you’ve blocked off in your robot.txt.
Use clean urls, and make sure to include a <lastmod> tag to let Googlebot get to the newest stuff first. You can prioritize this way, so when you have a large overhaul and a lot of new content you can get your most important pages indexed first.
Your text should look something like this:
If you are not enough of a code monkey to tweak this yourself, you can always go to Google themselves, or various other places on the Web, and have your site crawled and a map generated to submit to the search engines.
You can add a few more tags if you like, such as a <priority> tag if you feel that the <lastmod> tag will mislead the crawler, or a <change freq> to encourage the crawler to return daily, weekly or monthly. Don’t make up a number that’s fake, as they will consider that a reason to ignore you completely!
If you are using a sitemap generator, you will need to download the finished map to your computer and upload it into the “public_html/” folder of your site. Then you can go into your account and add your sitemap’s url.
Once Google has your map, they should crawl you soon and frequently. Just keep in mind that they have thousand on thousands of sites to crawl, and won’t waste time on something they can’t trust to give accurate information. Make sure all of your tags are accurate, and that you closed all of your tags with a [ / * * *].
There are many important things you can follow up on as often as possible, but keeping the attention of Google is a main necessity. Keep accurate, fresh content on your site at all times, and resubmit your site map if you feel you have been waiting too long.
Sitemaps can be invaluable to you when you are first setting up your site, and for years afterward. Whenever you update or change your content, you can rest assured that the search engine will index it quickly and accurately. This will encourage your rise through the SERPs.