Find some free tutorials in the following websites:
- Hackers Arise
- Kali Linux Hacking Video Tutorials
- Network Stuff -Very powerful network info gathering tools for Windows
- Introduction To Cryptography
- Cryptography Tutorial + Slides
- Handbook of Applied Cryptography – This ebook contains some free chapter from one of the popular cryptography books. The full book is also available on amazon at Cryptography Book.
- Network Penetration testing Guide
- How to hack anything in Java
- Mcafee on iPhone and iPad Security
- A Good Collection of White papers on security and vulnerabilities – This site contains collection of white papers from different sources and some of these white papers are really worth referring.
- Engineering Principles for Information Technology Security
- Basic Principles Of Information Protection
- Open Web Application Security Project – OWASP is one of the most popular sites that contains web application security related information .
Videos & Play Lists
- Cryptography Course By Dan Boneh Stanford University
- Open Security Training– Youtube Playlist of More than 90 hours. I have found this to be the biggest free training available for security related topic.
- OWASP AppSec USA 2011: Youtube Playlist containing compilation of OWASP conference highlight in 2011.
- Defcon: How I Met your Girlfriend – Defcon is one of the most popular hacker conference. The presenters in this conference are well know inside the hacking industry.
- Defcon: What happens when you steal a hackers computer
- Defcon: Nmap: Scanning the Internet
- Public Key Cryptography: Diffie-Hellman Key Exchange
- Web application Pen testing
- Intro to Scanning Nmap, Hping, Amap, TCPDump, Metasploit
Forums For Hackers And Security Professionals
Just like any other area, forums are really great help for learning from other experts. Hundreds of security experts and ethical/non-ethical hackers are willing to share their knowledge on forums for some reason. Please keep in mind to do enough research before post a question and be polite to people who take time to answer your question.