As Petey says. THEY should be backing it up for you if they are hosting it. Find someone who cares enough to do that for you.
Also, if you change a page, just save it before uploading it. That way you should have a copy of it on your machine as well. Just back up your copy. I keep a backup copy of our server on site and off site. If the building burns down, I've STILL got it!!! Rob
Just my $.02.