[dahark]

They make a huge difference my friend.

Sign up with the big three, and im not talking WW2 LOL history Joke
Google, MSN, Yahoo, they all have decent webmaster services that enable you to upload your site map. There are plenty of on-line sites that can do it for you and 3rd party software that will create site map for you. I think it is important to submit every page in a sitemap, but the oness with a lot of text are crucial, as search engine will be lookig for those crucial keywords that occur in your site. With site maps you can also set the priority of individual pages, on a scale of 1 - 0 , 1 being the highest, telling the crawlers which are the most important pages on your site.

With regard to actual site map for visitors yes only keep it to top level hierarchy maybe some secondary pages, but don't forget this site map will be index to so it can be hand to make sure its easy to access, and all the links are working/ correct. A good idea would be to put in a footer on your homepage and subsequent other pages.

Another point with site maps, submit the feeds, RSS and ATOM to key ones especially if your page is constantly changing you want to make sure these spiders are constantly checking your page.