A piece of advice??

Hello to everyone. I'm Alexis and as I'm new to cryptography I would appreciate a piece of advice. I've read the book "Applied Cryptography" by Bruce Schneier and I also have the "ICSA Guide to cryptography". However I would like to know where could I find more books related to cryptography. Also (if I'm not causing enough trouble already) as I'm trying to secure one system I would like to kindly ask for guidance. How do we apply an algorithm to a whole system? I know how to encode a message , but a system? I know I'm not being very specific, but I don't know much more myself. If it is not that much of a trouble, please enlighten me! Thanx in advance. Alexis