TwoFish links:

• Counterpane's TwoFish page

AES links:

• Dr. Brian Gladman's Cryptography Technology page.
• National Institute of Standards Advanced Encryption Standard competition page.
• The Block Cipher Lounge's AES page

General Cryptography Links:

• Applied Cryptography -- describes the various feedback modes in detail. A bit dated now, and doesn't have much info on public key encryption (sigh).

Export Regulations:

• The BXA regulations governing export of encryption source code. (basically: inform BXA that you have it on your web site, and anything source code can be exported).