Do you plan to add AES grade security to your contacts program?As you might be aware, encryption inside database is not desired regarding to performance, especially about searching data.
From comprehensive point of view, you also need to protect other data. Are you going to ask all vendors of programs of these data to add encryption to these programs? Obviously not, an quick and easy and cheap solution is to use Truecrypt, which is freeware, easy to use. I used it in my usb memory stick. Truecrypt uses AES, and can provide a secure storage for all your sensitive data and programs. Using Windows LUA settings and TrueCrypt, almost all your security issues will be resolved. Please search Truecrypt for details.