Wanna sell something? You need a sales letter. Now, before we get into the dirty argument of "McDonalds doesn't use sales letters", I want to say this: If you are a small seller of goods/services/products, a sales letter is vital. You don't have the massive budget to enact a million dollar marketing/branding campaign. In fact, a sales letter will help you convert your targeted traffic into sales. Now, I don't mean to brag...but... I'm pretty damn good at writing sales letters.