Especially considering Winston's observation, I'll direct you to the OWASP site. There are many different aspects of security some of which are process and procedure oriented. There is not "a" (single) solution and will go so far as to suggest there is no way to stop all spoofing. The OWASP site is a good place to go to understand what some of the various vulnerabilities are and provide some detailed awareness on the most common.
I’ve looked at a lot of different solutions, and in my humble opinion Aspose is the way to go. Here’s the link: http://aspose.com