Freelancers: Five Steps to Write a Cold Email That Converts New Clients | Observer
Options and sample emails for freelancers. These templates assume the writer has a blog and other social media channels to promote content for potential clients.
The Freelance Designer's Guide to Cold Emailing (with Templates) | Dribbble
Parts of this guide are maybe too general and not specific enough if you're just getting started, but the templates and example emails are helpful.