What email program/interface are you using? If you're using Gmail in a web
browser, for example, click Compose Email, the click Attach a file, which is
right under the Subject: field.
If you're using Windows Live Mail, click Attach, or click Insert - File as
attachment.
In Outlook, you can simply drag the file from a Windows Explorer window and
drop it into the email.
OK, but what if I want to send an attachment via Windows Live Mail by
clicking the email button in Word 2007. All I get is a fail message until
I've clicked and canceled three times.