This annotated guide on scientific ideas about communicating with alien civilizations is part of the education web pages of the nonprofit Astronomical Society of the Pacific.  As scientists continue to search for radio messages from intelligent life among the stars, serious interdisciplinary work is being done on the form that messages might take between civilizations that may not only have different languages, but even different biology.  In this resource guide, over 50 different books, articles, and web sites help readers
examine the issues of extra-terrestrial communication from the perspective of astronomy, linguistics, psychology, and computer programming.  Most of the resources are written for non-specialists.
Several of the web sites have interactive
features for designing and decoding messages.