I recently came across a great tool for working with Encrypted email.
Thunderbird is a great free email client for OS X and Windows
Enigmail is a free plug-in for Thunderbird that allows for sending and receiving encrypted email messages. You can also sign emails.
Once downloaded and installed you need to also install GnuPG tools:
“The first and most popular option is to use the MacGPG package by
gpgtools.org. They provide pre-built binaries of GnuPG 2.0.22 and later for
users running OS X 10.6 (Snow Leopard) or later. Download the GPG-Suite
from https://gpgtools.org/gpgsuite.html and install it. If you don’t
want to use the other components (Certificate Manager, Apple-Mail plugin and
Services application), you can deselect them during the installation process.
Only the MacGPG component is required for Enigmail.”
Sharing your Public Key (don’t share Private)
“Share your public key manually
On the Key Management window, select your key pair and click on File → Export Keys to File. Again, you will be asked whether you want to include your secret key in the saved OpenPGP key file: make sure you click on Export Public Keys Only this time. Save the ASC file, which will have a name like Firstname_Lastname_you@domain.com_(0x89ABCDEF)_pub.asc.
This is a copy of your public key; notice the “pub” word at the end of the filename. You can now put the file on your website for people to download it, or carry it around in a USB drive to distribute it to people, or send it via email as an attachment.
Concerning this last option, there is a simple Enigmail shortcut for it: when writing your mail in the Message Composition window, simply click on Attach My Public Key or choose from the menu bar Enigmail → Attach My Public Key and Enigmail will attach it upon sending.”