My parents used to live out in the country in southeast Louisiana. After Katrina, they had 50 large trees down on the property. I was living in Virginia at the time and drove home to help with cleanup. I hired two locals who needed work for $100/day each. I provided all the equipment.
Side note - I think that's when I bought the Poulan P295 saw new - ran for a week day in and day out with no issues. Cut up a LOT of very large oak trees.
Anyway, if you want a rough estimate, maybe start with you bringing in $200/day, just for general cleanup, chainsaw work. If you're bringing any more equipment, or doing anything else (stump grinding, hauling away stuff), add to it.
To those who cleaned up for free after storms, I agree that's what you do with neighbors, relatives, and friends. But I don't see anything wrong with hustling to make some $ after a storm hits, as long as you're not gouging anyone and trying to take advantage of a bad situation.