Comment Good start (Score 2) 333
Slashdot is a good forum to ask this type of question. I'm sure you'll find a few individuals who work securing financial systems, but you are probably better off having a one on one with someone with some real experience. Data security methodology will likely be a hot topic this year among management and security researchers, so you should check for conferences in your area, or budget some time to take a weekend or too off. I doubt a book will teach you everything (often year old information), so I strongly recommend you seek someone out for a short course or walk through. Also, be sure to sign up for a security list serve so you get the most up-to-date content and questions being asked.