Easy. Put this in your image folder:
AuthUserFile /dev/null
AuthGroupFile /dev/null
RewriteEngine On
RewriteCond %{HTTP_REFERER} !^
http://www.yourdomain.com.* [NC]
RewriteCond %{HTTP_REFERER} !^
http://yourdomain.com.* [NC]
RewriteRule /*
http://www.whereyouwanttoredirect.com/anypage.html [R,L]
It saves the folder where you put it and every folder inside it.
EDIT: You must save it as .htaccess. Use notepad and write the saving file name as ".htaccess". No .txt or .html or nothing. Then upload. You should see that file in your FTP as .htaccess
EDIT MORE: Hmmm...I'm not good in this. Remember that you must have this " in file name. So write ".htaccess" not .htaccess
EDIT EVEN MORE: Use this .htaccess only in folders that have images and graphics. If you put in folder that have HTML pages you're images and graphics won't show.