security depends on the language you use to a certain extent, but that doesn't replace common sense. I bet I could write you an insecure web app in VB .NET if I knew the language. I think it is more important to use a language you are familiar with, so the chance of you doing something stupid in the language are minimized.

PS: Not a technical book, but the best book on security I've read is 'Secrets and Lies' by Bruce Schneier, an eye-opener that made me realize security is not some technical specification.