JohnH writes:

http://tinyurl.com/hofoe

Definitely gives me second thoughts about subscribing. I think I'll just
stick with Cox and Yahoo.

You're confused. Any email address can be spoofed. This has nothing to do
with Gmail. It can happen with any compliant mail server, including the
alternatives you mention. It is in the nature of the Internet email
standards.

*Nothing* in an email message (neither body nor headers) can be trusted
except the topmost "Received:" header and the "From" timestamp (*not* the
"From" email address, nor the "From:" header)..