Location, Location, Location... an address defines a location! So what makes a good address?
Your email provider determines a critical element of your address: the domain. Let's look at the kinds of providers.
Work, school and other organizations provide email accounts. These accounts have an address that will carry that group's domain, in most cases. You may purchase your own domain or website and select an email provider. Also, the big Internet players offer free email accounts, like Google, Microsoft, Yahoo and AOL, for examples. Internet Service Providers (ISPs) also offer email accounts as part of their services, such as Comcast, Cox, Verizon and AT&T.
For personal email accounts, I recommend Google's Gmail. Microsoft also offers free email with the domains outlook.com and hotmail.com. Many use Yahoo or AOL.
Most people want to have one personal email address. I recommend using an address domain that is not connected to work or school or ISP or any other affiliation. That way, when changing jobs or moving to a new home, you don't need to change your email address.
If you are so motivated, you can maintain your own email account. If you are doubly motivated, like say Hillary Clinton, you might run your own email server in the basement or safe room.