Google Sitemap Help

[greent]

I'd like to submit an xml sitemap to google. Rather then having to manually create one each time I write up a blog entry, is there any way to automate it?

Also, I don't get a lot of comments on my site, but I do get some. Regarding the question asks about how often the page is updated, what would be the appropriate answer for a blog? I don't want google to ignore the page because I say it's updated infrequently yet I don't want to say updated daily due to fear of a ban.