The thing I've noticed with Craigslist rooms for rent is if you find a decent deal and situation, you need to be able jump on it right right away or it will be gone. Usually the ads get more serious with email/callbacks towards the latter half of the month as lease-holders start to poop their pants at the prospect of having to cover the expense of an empty room out of pocket for a month. Most of them don't wanna hear you cant move in till say, Nov 1st when it's Sept 22nd...they want somebody for Oct 1st if somebody ditched out on them, or they were too much of a bonehead to get their ducks lined out early. This means you needed to have your 30 day notice in to your current landlord at the
beginning of the month if you want your deposit back and for everything to be on the up and up. This is obviously dicey since there is a chance you wont find a place and your current room will be rented out from under you, but you can also scan for ads that are working far enough ahead to not put you in danger of that happening.
Yeah, apt and roommate hunting is almost as bad as job hunting. I'm looking forward to the day I can sign a lease on my own place and not have to bother with all the rest of it.