Depends on where you're starting from. Is sales something you've done previously and you're currently doing with some success but want to be better? Or are you a technical founder who doesn't feel comfortable selling but want the challenge and know you can be great at it, if provided the support? Or something else entirely?
There is no one formula, despite what the publishing and coaching industry says!
I'd encourage you to re-post or edit the question with more details so I can answer it in more detail, or I'm happy to a call with you to understand what you're looking to achieve and provide you some suggestions.
Jeffrey Gitomer has a great series of little books like his Little Red Book of Sales Answers. Other superb books I'd recommend are Ian Altman's Upside Down Selling and Harry Beckwith's Selling the Invisible as well as Karl Albrecht's Service America.
My own book, Seal the Deal, could be useful to you as it distinguishes networking, marketing, and sales for a service professional and outlines a system for how to leverage the essential mindsets in each one for integrated action. It's not written specifically for CEOs, though, so you may not want that.
You might also check out Bill Cates' newest book: Beyond Referrals.
As for courses, there are a wide array of excellent offerings available on udemy.com on every topic under the sun!
You might also consider hiring an executive coach. Stanford just released a study about the value of CEOs having a coach: http://www.suzipomerantz.com/stanford-executive-coaching-study-reveals-most-ceos-want-coaching/
"How to Win Friends and Influence People". Written by Dale Carnegie. (also available as an audiobook)
More of a sales philosophy.
I tend to be very skeptical towards sales books that seem to hold the perfect answer for any given situation.
Hope this helps
Sales is about applied knowledge. There are a ton of great books, many of them previously listed. A couple that have recently read, that really resonated, were "The Challenger Sale" and Dan Pink's "To Sell is Human".
Read, then apply, then read again, and re-apply. Put yourself out there, understand rejection is not personal, rather a chance to improve. Anyone can be a great salesperson if they approach it like learning any other skill. Good luck!