At one time, a copyright notice was required to protect a copyright,
but this is no longer the case. However, whether you register your
copyright or not, it's a good idea to display notice on copies of
unpublished work that effectively leave your control - for instance, if you decide to offer an excerpt on your web site, or post work to an online newsgroup.
It probably isn't necessary to use a copyright notice when
submitting work to reputable publishers and literary agents; they
understand that it's cheaper to pay you for your work than it is to
fight a lawsuit and/or risk their reputations. More than likely, the
only thing you'll accomplish by placing a copyright notice on your
submission to an editor or agent is to mark yourself out as an amateur.
If you choose to include a copyright notice on your work, the proper
form of notice includes all of the following three elements:
The year (For published works, this would be the year of first
publication; however, there is no definitive information as to what
year should be used for unpublished works, so I always use the current
year.)
The notice should appear in such a way as to give reasonable notice
that copyright is claimed - such as next to the title. As long as this
requirement is met, a court will give no weight to an infringer's
defense of "innocent infringement" - that is, that she was unaware the
work was protected.