http://www.BlockShopper.com is a good resource. You can also search the Palm Beach County property appraisers database, click on search, then Advanced Search. There is a section for Sales and choose a community or development (Madison Green). There are several plats in Madison Green, so you may have to work a little harder.
I hope this helps. Visit http://www.NewFLproperties.com
I am a resident of Madison Green.