There is a site called http://corz.org/ which contains some very useful,original and accurate htaccess tips and tricks at http://corz.org/serv/tricks/htaccess.php which if you scroll down it you will see that, as Simon rightly says, you can get away with the simplest of lines such as:-
If you have no friends
deny from all
or if you have a whole friend
allow from xxx.xxx.xxx.xxx
So you see, the line from scjessey in his post, ideally suits your needs.
deny from xxx.xxx.xxx.xxx
You can add other entries into an .htaccess file, as per the excellent examples at http://corz.org/ , as you need them.
Opinions are my own views, not DreamHosts'.
I am NOT a DreamHost employee OK! :@
Act on my advice at your own risk!