University of Wisconsin
University of Wisconsin Madison: Sea and Land Breezes
This site from the University of Wisconsin-Madison contains a medium length article on sea and land breezes. Throughout the article links are provided for additional information on related subjects. A picture is also given.
University of Illinois
University of Illinois Urbana Champaign: Ww2010: Forces and Winds: Pressure Gradient Force
Explains what a pressure gradient is and how it produces air movement.