Want to stop a certain visitor from coming to your site? If you have their IP adress, you can. Copy the code below, and paste into notepad (start>>programs>>accessories>>notepad). Change 00.000.00.00 to the IP address of the person you want to block. Name this file .htaccess and make sure it doesn't have an extension on the end, like .txt. If it is named .htaccess.txt, rename it .htaccess. Save it and upload it to your main directory. Or, you can upload it as .htaccess.txt, and rename it when it's on your server. If you already have a .htaccess file in your directory, because you have a custom 404 page or something, just put the code beneath whatever you already have.