We are working on second edition of PostGIS in Action 2ed for availability sometime in late 2013/early 2014. Early purchase review (MEAP) is now available for Second Edition. With MEAP you can get chapter updates as we write them and get the final polished copy at release time.
Our most recent book PostgreSQL: Up and Running is out in both E-book and hard-copy. You can order hard-copy now from Amazon or Kindle or hard-copy or e-Book from O'Reilly .
PostGIS Online is a project started by Nicklas Avén.
This site will allow you to dynamically try PostGIS SQL statements on line without even installing PostGIS. You can try some of the examples in chapter 2 of our book that are self standing examples and watch these dynamically displayed on a map.
For example type in an SQL statement such as:
SELECT ST_GeomFromText('POLYGON((-0.25 -1.25,-0.25 1.25,2.5 1.25,2.5 -1.25,-0.25 -1.25), (2.25 0,1.25 1,1.25 -1,2.25 0), (1 -1,1 1,0 0,1 -1))') As the_geom
Then click the Map 1 button and watch as the geometry is drawn on the screen.
