Information on name to work under

1. If I wanted to write a novel underneath a pseudonym and I wanted to
register the name, how do I go about that?

2. Can I make that private so that no one else has access to it?

3. In the event that I feel someone is being a voyeur or hacking into my
information or my computer what actions can I take to protect myself if I
don\'t have information on them and where do I obtain it?

You can register a name or trade name.

You can have police review internet logs etc. if somebody really is breaking in to the accounts...

How do you go about registering a name and/or trade name? Is there anyplace on the internet or in the public library I could look up what to do? Also is there any specific paperwork I need to see? Do I need an attorney to help me do this or am I able to go to a law clinic or by myself?
Also, if I have already started writing and want to write underneath this name is that okay to do so or do I have to worry about problems?