Funny to see this post, I just got done cutting my crown moldings for a bathroom. I wouldn't try it without a power miter saw. If you buy one make sure it can handle the height/width of your molding, there are limits. I'm coping the inside corners and a dremel tool works great to sand away the back of the molding for a tight fit. With crooked walls it's difficult to guarantee a nice 45 degree angle. My saw isn't a compound miter and it works great with the molding I have. I referenced a Home Depot Home Improvement 1-2-3 book and it gives some great tips.
Any suggestions out there on how to fill in the gaps between the ceiling and the molding? Unfortunately my ceiling isn't perfectly flat.