http://www.javaranch.com/
http://www.javapassion.com/
http://java.sun.com/javaee/5/docs/tutorial/doc/
http://java.dzone.com/
http://www.ibm.com/developerworks/java/
http://www.java.net/
http://www.sun.com/training/catalog/java/index.xml
http://forums.java.net/jive/index.jspa
http://developers.sun.com/learning/javaoneonline/
http://www.particle.kth.se/~lindsey/JavaCourse/Book/index.html
The two books I would highly recommend:
Bruce Eckel's Thinking in Java, 4th Edition
Agile Java Development with Spring, Hibernate and Eclipse by Anil Hemrajani
Additionally, it is worthwhile to spend some time reading the following books that are available on the Sun Developer Network (SDN):
The Java Language Specification
