Deny website to certain ips

Add the following to your .htaccess:

<Files 403.shtml>
order allow,deny
allow from all
</Files>

deny from 10.5.3.33

This will block the ip from accessing the site.

To block a range 10.5.3.3-10.5.3.40:

<Files 403.shtml>
order allow,deny
allow from all
</Files>

deny from 10.5.3.3/32
deny from 10.5.3.4/30
deny from 10.5.3.8/29
deny from 10.5.3.16/28
deny from 10.5.3.32/29
deny from 10.5.3.40/32