Here are some security resources that I have found to be of the highest quality.
"Secrets And Lies" by Bruce Schneiner
If you buy one book on security, get this one.
"Beyond Fear" by Bruce Schneiner
If you buy two books on security, get this along with the above...
"The Art Of Deception" by Kevin Mitnik
"Hackers' Handbook 3.0" By Dr. K
"Security Engineering" by Ross Anderson
"Hacking Exposed Series" by various authors
"The Best of 2600: A Hacker Odyssey" edited by Emmanuel Goldstein
"Applied Cryptography" by Bruce Schneiner
"Hacking: The Art Of Exploitation" by Jon Erickson
I also recommend attending the CCC in Berln and HOPE in New York. See www.ccc.de and www.hope.net for details.
If you are in Tokyo come along to a Tokyo 2600 meeting. www.tokyo2600.net