If the bunny is smaller than the size of an apple, and/or his eyes are closed, then he is still nursing. This is a critical stage. If you cannot find a rehabber right away, you may try to feed the bunny on a temporary basis. It's best to feed the bunny water or Pedialyte for the first feeding, and to dilute the formula (listed below) with Pedialyte for the next couple of feedings, to gradually introduce the formula. Here is a home-made formula you may use:

4 fluid ounces of canned evaporated milk
4 fluid ounces of water
1 tablespoon of Karo Syrup
One egg

DO NOT feed regular milk in any case!

To feed the bunny, put the formula in a plastic eyedropper and place a few drops at a time on the bunny's lips - bunnies will not take to sucking right away. Again, you need to find a rehabber who can give you advice in this area, or who can take the bunny. If you do not have training in this area, or do not get advice from a wildlife rehabilitator, then you increase the chances that the the bunny will die.

You also need to stimulate eyes-closed bunnies to urinate, by gently rubbing their genital area with a warm, wet cottonball for a few moments.