You might want to not wait too long although you can sometimes get deals if you wait till the last minute. I spoke with a girl who got her photographer for about $200 less b/c she waited until 3 weeks before. It was definitely a risk but if you are on a tight budget, it could be a great reward. Also, depends on the day. If you marry on a mon to thurs, there is more avail. Hope this helps.
Heather