Removing rocks in going to be a process no matter what you do. It might be worth it so set up one or two raised beds to use while you're working on the larger garden plot. They'll dry out quicker in the spring, allowing you to get a jump on the gardening season, also--it's easy to set up mini hoop-houses with a raised bed, to extend your season into the fall.
To remove the rock in your larger plot, you can start with a rake and pry bar for rock on the surface, and use a wheelbarrow to move them away from the garden spot.
To remove rocks beneath the surface garden tractors (if you're so fortunate to have one) come with a number of different attachments, such as grading blades, heavy duty plows, and large gardening rakes. If you do not have access to a tractor, try loosening the soil with a rototiller, use a garden fork, or the tried and true shovel.
Finally, a soil sieve or screen can be used to sift the soil to eliminate the smaller rocks.
Check out this link for more info: http://www.ehow.com/info_8000785_tool...