Here are the steps to grabbing anyone's email off Linkedin:

1. Install Chrome browser https://www.google.com/chrome/
2. Install Email Hunter extension https://emailhunter.co/chrome
3. Head to Linkedin.com and search for CFO
4. Next to the connect button on their profile, you will see a new button with a target icon, click that.
5. Their email should appear most of the time. Sometimes you have to type in the URL of the company they are with now.

Note: You will rarely receive a positive response from anyone after a cold email. Hopefully what you are offering in return for opening your email (valuable proposition or opportunity) is enough for them to want to reply. I would begin the email in an apologetic fashion regardless;
"Hello _____,

I would first like to apologize for the cold email. I myself hate receiving them, but I found your experience to be an exact fit for _____ so I had to reach out via email...."

Enjoy :)