I can post some links and warn you that very large .htaccess files can cause issues just not good to have imo.
http://www.webdeveloper.com/forum/sh...d.php?t=133633
http://www.wizcrafts.net/nigerian-blocklist.html
Basically your looking at some editing on the htaccess end and I've honestly never thought to do anything this extreme as for me anyone visiting could be a potential client etc so I can't speak from experience perhaps leave time for someone else to chime in and possibly help with this or use those links and Google to find something you can use

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