Just drive around your neighborhood and look for the eggs for sale signs. Many people put them in front of their driveways for $5 or $6 a dozen. Usually in a cooler with an "honor system" cashbox nearby.
Most people with a chicken coop in their backyard produce too many eggs for personal use and so are happy to put them out front to make a little bit of cash. You just have to keep an eye out for the signs.
