I would highly recommend that you buy a book. I started learning Java with
Core Java Volume 1. This book has recently been revised for the newest version of Java, Java 5. However, if you insist on online resources, you can start with
Sun's online tutorials. I especially recommend "Your First Cup of Java".
You should also check out Bruce Eckel's
Thinking in Java. There are plenty of other resources, printed as well as online, you should google for it or visit your favorite local or online bookstore.
HTH
Layne