Hi, I have come to US on H4 visa with my husband, who holds H1B visa. Unfortunately the things are not working out and we are planning to file for divorce. So I currently stay at my Uncle's place. But I want to know one thing, can my husband inform the INS and get my H4 visa cancelled on the grounds that I am not staying with him?

No. It terminates upon your divorce, not your separation. Of course, if fraud was involved it's a different story.

You cannot work on an H4 visa, of course.