Another Java magazine is JavaWorld. Lots of applets, resources, links. Gamelan's going to have a challenge to be the most up to date collection of resources these days.
For programmers, check out the Java Class Warehouse, a repository of free, reusable user-contributed classes for Java.
A nice reference for Java books is the Definitive HTML Book List, which features all the Java books released so far, as well as almost every Web related book in existence.
If you're looking for Java resources in the UK, check out the Java Centre
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