(2-part post):
I think this question has been sitting here unanswered for a couple of days because we're all rather confused. I'm still confused but I'll have a stab at it anyway. (After reading it, you might need to post again, to clarify your question).
What isn't really clear is exactly what type of email service you're referring to. If you simply buy a domain name, like www.moodymann.com, you don't get any email facilities with it. (So, no matter how you configure Outlook Express, you won't be able to use any '@moodymann.com' addresses)
However, the firm through which you registered the domain name will probably have offered you (for more money) a choice of 'mail forwarding' or a full 'SMTP/POP3' mail service.
If you accepted 'mail forwarding', you'll be able to receive mail sent to, say, '
[email protected]'. However, there's no specific mailbox for it. Such mail is simply forwarded to your 'normal' email address, such as
[email protected]. When you reply to emails, you'll continue to use your 'normal' account (and the people receiving your mail will see your 'real' address, rather than the shop one).
So, if you've got 'mail forwarding', you shouldn't be doing anything with Outlook Express, since everything will come and go through your existing btconnect account.